Fix creating a local project in the right folder (#5621 )

Bump to 5.2.172 (#5620 )
Update translations [skip ci] (#5614 )
2025-10-15 10:19:04 +00:00 · 2023-09-01 17:46:47 +02:00 · 2023-09-01 14:32:32 +02:00 · 2023-09-01 14:30:07 +02:00 · 2023-09-01 13:58:51 +02:00 · 2023-09-01 09:57:51 +02:00
756 changed files with 65496 additions and 49608 deletions
--- a/.circleci/config.yml
+++ b/.circleci/config.yml
@@ -15,7 +15,7 @@ jobs:
  # Build the **entire** app for macOS.
  build-macos:
    macos:
-      xcode: 12.5.1
+      xcode: 14.2.0
    steps:
      - checkout

@@ -64,11 +64,11 @@ jobs:
      # Note: Code signing is done using CSC_LINK (see https://www.electron.build/code-signing).
      - run:
          name: Build GDevelop IDE
-          command: export NODE_OPTIONS="--max-old-space-size=7168" && cd newIDE/electron-app && npm run build -- --mac --publish=never
+          command: export NODE_OPTIONS="--max-old-space-size=7168" && cd newIDE/electron-app && CI=false npm run build -- --mac --publish=never

      - run:
          name: Clean dist folder to keep only installers/binaries.
-          command: rm -rf "newIDE/electron-app/dist/mac/GDevelop 5.app" && rm -rf "newIDE/electron-app/dist/mac-arm64/GDevelop 5.app"
+          command: rm -rf "newIDE/electron-app/dist/mac-universal/GDevelop 5.app"

      # Upload artifacts (CircleCI)
      - store_artifacts:
@@ -101,8 +101,8 @@ jobs:
          command: sudo apt-get update && sudo apt install cmake

      - run:
-         name: Install Python3 dependencies for Emscripten
-         command: sudo apt install python-is-python3 python3-distutils -y
+          name: Install Python3 dependencies for Emscripten
+          command: sudo apt install python-is-python3 python3-distutils -y

      - run:
          name: Install Emscripten (for GDevelop.js)
@@ -178,8 +178,8 @@ jobs:
          command: sudo apt-get update && sudo apt install cmake

      - run:
-         name: Install Python3 dependencies for Emscripten
-         command: sudo apt install python-is-python3 python3-distutils -y
+          name: Install Python3 dependencies for Emscripten
+          command: sudo apt install python-is-python3 python3-distutils -y

      - run:
          name: Install Emscripten (for GDevelop.js)
--- a/.devcontainer/devcontainer.json
+++ b/.devcontainer/devcontainer.json
@@ -0,0 +1,14 @@
+{
+  "image": "mcr.microsoft.com/devcontainers/universal:2",
+  "onCreateCommand": "cd newIDE/app && npm install && cd ../electron-app && npm install",
+  "forwardPorts": [3000],
+  "customizations": {
+    "vscode": {
+      "extensions": [
+        "esbenp.prettier-vscode",
+        "ms-vscode.cpptools",
+        "flowtype.flow-for-vscode"
+      ]
+    }
+  }
+}
--- a/.github/workflows/build-storybook.yml
+++ b/.github/workflows/build-storybook.yml
@@ -9,6 +9,10 @@ name: Build Storybook
 on:
  # Launch on all commits.
  push:
+    branches:
+      - "**"
+    tags-ignore:
+      - "**" # Don't run on new tags
  # Allows to run this workflow manually from the Actions tab,
  # to publish on Chromatic (not done by default).
  workflow_dispatch:
@@ -24,8 +28,8 @@ jobs:
      - uses: actions/setup-node@v3
        with:
          node-version: 16
-          cache: 'npm'
-          cache-dependency-path: 'newIDE/app/package-lock.json'
+          cache: "npm"
+          cache-dependency-path: "newIDE/app/package-lock.json"

      - name: Configure AWS Credentials
        uses: aws-actions/configure-aws-credentials@v2
--- a/.github/workflows/extract-translations.yml
+++ b/.github/workflows/extract-translations.yml
@@ -4,6 +4,10 @@ name: Extract translations
 on:
  # Execute for all commits (to ensure translations extraction works)
  push:
+    branches:
+      - "**"
+    tags-ignore:
+      - "**" # Don't run on new tags
  # Allows to run this workflow manually from the Actions tab.
  workflow_dispatch:

@@ -15,8 +19,8 @@ jobs:
      - uses: actions/setup-node@v3
        with:
          node-version: 16
-          cache: 'npm'
-          cache-dependency-path: 'newIDE/app/package-lock.json'
+          cache: "npm"
+          cache-dependency-path: "newIDE/app/package-lock.json"

      - name: Install gettext
        run: sudo apt update && sudo apt install gettext -y
--- a/.github/workflows/update-translations.yml
+++ b/.github/workflows/update-translations.yml
@@ -7,6 +7,8 @@ on:
  push:
    branches:
      - master
+    tags-ignore:
+      - "**" # Don't run on new tags
  # Allows to run this workflow manually from the Actions tab.
  workflow_dispatch:

@@ -18,8 +20,8 @@ jobs:
      - uses: actions/setup-node@v3
        with:
          node-version: 16
-          cache: 'npm'
-          cache-dependency-path: 'newIDE/app/package-lock.json'
+          cache: "npm"
+          cache-dependency-path: "newIDE/app/package-lock.json"

      - name: Install gettext
        run: sudo apt update && sudo apt install gettext -y
--- a/.vscode/settings.json
+++ b/.vscode/settings.json
@@ -1,131 +1,134 @@
 // Place your settings in this file to overwrite default and user settings.
 {
-    "files.associations": {
-        "*.idl": "java",
-        "Fastfile": "ruby",
-        "iosfwd": "cpp",
-        "functional": "cpp",
-        "type_traits": "cpp",
-        "utility": "cpp",
-        "algorithm": "cpp",
-        "random": "cpp",
-        "__config": "cpp",
-        "cstddef": "cpp",
-        "exception": "cpp",
-        "initializer_list": "cpp",
-        "new": "cpp",
-        "stdexcept": "cpp",
-        "typeinfo": "cpp",
-        "*.tcc": "cpp",
-        "cctype": "cpp",
-        "clocale": "cpp",
-        "cmath": "cpp",
-        "complex": "cpp",
-        "cstdarg": "cpp",
-        "cstdio": "cpp",
-        "cstdlib": "cpp",
-        "ctime": "cpp",
-        "cwchar": "cpp",
-        "cwctype": "cpp",
-        "istream": "cpp",
-        "limits": "cpp",
-        "memory": "cpp",
-        "ostream": "cpp",
-        "sstream": "cpp",
-        "streambuf": "cpp",
-        "hashtable": "cpp",
-        "tuple": "cpp",
-        "unordered_map": "cpp",
-        "unordered_set": "cpp",
-        "__split_buffer": "cpp",
-        "deque": "cpp",
-        "iterator": "cpp",
-        "list": "cpp",
-        "map": "cpp",
-        "queue": "cpp",
-        "regex": "cpp",
-        "set": "cpp",
-        "stack": "cpp",
-        "string": "cpp",
-        "vector": "cpp",
-        "iostream": "cpp",
-        "__functional_03": "cpp",
-        "__hash_table": "cpp",
-        "__tree": "cpp",
-        "bitset": "cpp",
-        "__bit_reference": "cpp",
-        "__mutex_base": "cpp",
-        "fstream": "cpp",
-        "ios": "cpp",
-        "__locale": "cpp",
-        "valarray": "cpp",
-        "freeglut_spaceball.c": "cpp",
-        "__tuple": "cpp",
-        "hash_map": "cpp",
-        "hash_set": "cpp",
-        "system_error": "cpp",
-        "__nullptr": "cpp",
-        "__functional_base": "cpp",
-        "__functional_base_03": "cpp",
-        "chrono": "cpp",
-        "ratio": "cpp",
-        "atomic": "cpp",
-        "locale": "cpp",
-        "string_view": "cpp",
-        "__string": "cpp",
-        "cstring": "cpp",
-        "iomanip": "cpp",
-        "cstdint": "cpp",
-        "forward_list": "cpp",
-        "mutex": "cpp",
-        "__hash": "cpp",
-        "__debug": "cpp",
-        "__threading_support": "cpp",
-        "any": "cpp",
-        "array": "cpp",
-        "cinttypes": "cpp",
-        "numeric": "cpp",
-        "__memory": "cpp",
-        "__errc": "cpp",
-        "__node_handle": "cpp",
-        "bit": "cpp",
-        "optional": "cpp",
-        "filesystem": "cpp",
-        "compare": "cpp",
-        "concepts": "cpp",
-        "xfacet": "cpp",
-        "xhash": "cpp",
-        "xiosbase": "cpp",
-        "xlocale": "cpp",
-        "xlocinfo": "cpp",
-        "xlocmon": "cpp",
-        "xlocnum": "cpp",
-        "xloctime": "cpp",
-        "xmemory": "cpp",
-        "xstddef": "cpp",
-        "xstring": "cpp",
-        "xtr1common": "cpp",
-        "xtree": "cpp",
-        "xutility": "cpp",
-        "xlocbuf": "cpp",
-        "xlocmes": "cpp",
-        "xmemory0": "cpp",
-        "memory_resource": "cpp"
-    },
-    "files.exclude": {
-        "Binaries/*build*": true,
-        "Binaries/Output": true,
-        "GDJS/Runtime-dist": true,
-        "docs": true,
-        "newIDE/electron-app/dist": true,
-        "newIDE/app/build": true,
-        "newIDE/app/resources/GDJS": true,
-        "newIDE/electron-app/app/www": true
-    },
-    // Support for Flowtype (for newIDE):
-    "javascript.validate.enable": false,
-    "flow.useNPMPackagedFlow": true,
+  "files.associations": {
+    "*.idl": "java",
+    "Fastfile": "ruby",
+    "iosfwd": "cpp",
+    "functional": "cpp",
+    "type_traits": "cpp",
+    "utility": "cpp",
+    "algorithm": "cpp",
+    "random": "cpp",
+    "__config": "cpp",
+    "cstddef": "cpp",
+    "exception": "cpp",
+    "initializer_list": "cpp",
+    "new": "cpp",
+    "stdexcept": "cpp",
+    "typeinfo": "cpp",
+    "*.tcc": "cpp",
+    "cctype": "cpp",
+    "clocale": "cpp",
+    "cmath": "cpp",
+    "complex": "cpp",
+    "cstdarg": "cpp",
+    "cstdio": "cpp",
+    "cstdlib": "cpp",
+    "ctime": "cpp",
+    "cwchar": "cpp",
+    "cwctype": "cpp",
+    "istream": "cpp",
+    "limits": "cpp",
+    "memory": "cpp",
+    "ostream": "cpp",
+    "sstream": "cpp",
+    "streambuf": "cpp",
+    "hashtable": "cpp",
+    "tuple": "cpp",
+    "unordered_map": "cpp",
+    "unordered_set": "cpp",
+    "__split_buffer": "cpp",
+    "deque": "cpp",
+    "iterator": "cpp",
+    "list": "cpp",
+    "map": "cpp",
+    "queue": "cpp",
+    "regex": "cpp",
+    "set": "cpp",
+    "stack": "cpp",
+    "string": "cpp",
+    "vector": "cpp",
+    "iostream": "cpp",
+    "__functional_03": "cpp",
+    "__hash_table": "cpp",
+    "__tree": "cpp",
+    "bitset": "cpp",
+    "__bit_reference": "cpp",
+    "__mutex_base": "cpp",
+    "fstream": "cpp",
+    "ios": "cpp",
+    "__locale": "cpp",
+    "valarray": "cpp",
+    "freeglut_spaceball.c": "cpp",
+    "__tuple": "cpp",
+    "hash_map": "cpp",
+    "hash_set": "cpp",
+    "system_error": "cpp",
+    "__nullptr": "cpp",
+    "__functional_base": "cpp",
+    "__functional_base_03": "cpp",
+    "chrono": "cpp",
+    "ratio": "cpp",
+    "atomic": "cpp",
+    "locale": "cpp",
+    "string_view": "cpp",
+    "__string": "cpp",
+    "cstring": "cpp",
+    "iomanip": "cpp",
+    "cstdint": "cpp",
+    "forward_list": "cpp",
+    "mutex": "cpp",
+    "__hash": "cpp",
+    "__debug": "cpp",
+    "__threading_support": "cpp",
+    "any": "cpp",
+    "array": "cpp",
+    "cinttypes": "cpp",
+    "numeric": "cpp",
+    "__memory": "cpp",
+    "__errc": "cpp",
+    "__node_handle": "cpp",
+    "bit": "cpp",
+    "optional": "cpp",
+    "filesystem": "cpp",
+    "compare": "cpp",
+    "concepts": "cpp",
+    "xfacet": "cpp",
+    "xhash": "cpp",
+    "xiosbase": "cpp",
+    "xlocale": "cpp",
+    "xlocinfo": "cpp",
+    "xlocmon": "cpp",
+    "xlocnum": "cpp",
+    "xloctime": "cpp",
+    "xmemory": "cpp",
+    "xstddef": "cpp",
+    "xstring": "cpp",
+    "xtr1common": "cpp",
+    "xtree": "cpp",
+    "xutility": "cpp",
+    "xlocbuf": "cpp",
+    "xlocmes": "cpp",
+    "xmemory0": "cpp",
+    "memory_resource": "cpp",
+    "__bits": "cpp",
+    "__verbose_abort": "cpp",
+    "variant": "cpp"
+  },
+  "files.exclude": {
+    "Binaries/*build*": true,
+    "Binaries/Output": true,
+    "GDJS/Runtime-dist": true,
+    "docs": true,
+    "newIDE/electron-app/dist": true,
+    "newIDE/app/build": true,
+    "newIDE/app/resources/GDJS": true,
+    "newIDE/electron-app/app/www": true
+  },
+  // Support for Flowtype (for newIDE):
+  "javascript.validate.enable": false,
+  "flow.useNPMPackagedFlow": true,

-    // Clang format styling (duplicated in scripts/CMakeClangUtils.txt)
-    "C_Cpp.clang_format_style": "{BasedOnStyle: Google, BinPackParameters: false, BinPackArguments: false}"
+  // Clang format styling (duplicated in scripts/CMakeClangUtils.txt)
+  "C_Cpp.clang_format_style": "{BasedOnStyle: Google, BinPackParameters: false, BinPackArguments: false}"
 }
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -1,100 +1,99 @@
-#This is the CMake file used to build GDevelop.
-#For more information, see the README.md file.
+# This is the CMake file used to build GDevelop.
+# For more information, see the README.md file.

-cmake_minimum_required(VERSION 2.6)
-cmake_policy(SET CMP0011 NEW)
+cmake_minimum_required(VERSION 3.5)

 # Add utility functions
 include(scripts/CMakeClangUtils.txt) # To add clang-format and clang-tidy support to a target

 # Macro for defining an option
 macro(gd_set_option var default type docstring)
-    if(NOT DEFINED ${var})
-        set(${var} ${default})
-    endif()
-    set(${var} ${${var}} CACHE ${type} ${docstring} FORCE)
+	if(NOT DEFINED ${var})
+		set(${var} ${default})
+	endif()
+	set(${var} ${${var}} CACHE ${type} ${docstring} FORCE)
 endmacro()
+
+# Set options
 gd_set_option(BUILD_CORE TRUE BOOL "TRUE to build GDevelop Core library")
 gd_set_option(BUILD_GDJS TRUE BOOL "TRUE to build GDevelop JS Platform")
 gd_set_option(BUILD_EXTENSIONS TRUE BOOL "TRUE to build the extensions")
 gd_set_option(BUILD_TESTS TRUE BOOL "TRUE to build the tests")

 # Disable deprecated code
-set(NO_GUI TRUE CACHE BOOL "" FORCE) #Force disable old GUI related code.
+set(NO_GUI TRUE CACHE BOOL "" FORCE) # Force disable old GUI related code.

-#Setting up installation directory, for Linux (has to be done before "project" command).
-IF(NOT WIN32)
-	if (NOT APPLE)
-	gd_set_option(GD_INSTALL_PREFIX "/opt/gdevelop/" STRING "The directory where GDevelop should be installed")
-	ELSE()
-	gd_set_option(GD_INSTALL_PREFIX "." STRING "The directory where GDevelop should be installed")
-	ENDIF()
+# Setting up installation directory, for Linux (has to be done before "project" command).
+if(NOT WIN32)
+	if(NOT APPLE)
+		gd_set_option(GD_INSTALL_PREFIX "/opt/gdevelop/" STRING "The directory where GDevelop should be installed")
+	else()
+		gd_set_option(GD_INSTALL_PREFIX "." STRING "The directory where GDevelop should be installed")
+	endif()

-	#As we embed SFML, prevent it to be installed system-wide
+	# As we embed SFML, prevent it to be installed system-wide
 	set(CMAKE_INSTALL_PREFIX "${GD_INSTALL_PREFIX}/useless")
-ENDIF()
+endif()

 project(GDevelop)
 set(CMAKE_EXPORT_COMPILE_COMMANDS ON)
-IF(NOT WIN32 AND NOT APPLE AND NOT BUILD_TESTS)
-	SET(CMAKE_SKIP_BUILD_RPATH  TRUE) #Avoid errors when packaging for linux.
-ENDIF()
-IF(APPLE)
+if(NOT WIN32 AND NOT APPLE AND NOT BUILD_TESTS)
+	set(CMAKE_SKIP_BUILD_RPATH TRUE) # Avoid errors when packaging for linux.
+endif()
+if(APPLE)
 	set(CMAKE_MACOSX_RPATH 1)
 	set(CMAKE_INSTALL_RPATH_USE_LINK_PATH FALSE)
 	set(CMAKE_INSTALL_RPATH ".")
 	set(CMAKE_BUILD_WITH_INSTALL_RPATH TRUE)
-	set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -D_WCHAR_H_CPLUSPLUS_98_CONFORMANCE_")
-	set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wno-potentially-evaluated-expression")
-ENDIF()
-#Sanity checks
-IF ("${CMAKE_BUILD_TYPE}" STREQUAL "")
-	message( "CMAKE_BUILD_TYPE is empty, assuming build type is Release" )
+	add_compile_options(
+		-D_WCHAR_H_CPLUSPLUS_98_CONFORMANCE_
+		-Wno-potentially-evaluated-expression)
+endif()
+# Sanity checks
+if("${CMAKE_BUILD_TYPE}" STREQUAL "")
+	message(STATUS "CMAKE_BUILD_TYPE is empty, assuming build type is Release")
 	set(CMAKE_BUILD_TYPE Release)
-ENDIF()
+endif()

-IF("${CMAKE_BUILD_TYPE}" STREQUAL "Release" AND NOT WIN32 AND CMAKE_COMPILER_IS_GNUCXX)
-	SET(CMAKE_SHARED_LINKER_FLAGS "-s") #Force stripping to avoid errors when packaging for linux.
-ENDIF()
+if("${CMAKE_BUILD_TYPE}" STREQUAL "Release" AND NOT WIN32 AND CMAKE_COMPILER_IS_GNUCXX)
+	set(CMAKE_SHARED_LINKER_FLAGS "-s") # Force stripping to avoid errors when packaging for linux.
+endif()

 #Activate C++11
-include(CheckCXXCompilerFlag)
-CHECK_CXX_COMPILER_FLAG("-std=gnu++11" COMPILER_SUPPORTS_CXX11)
-CHECK_CXX_COMPILER_FLAG("-std=gnu++0x" COMPILER_SUPPORTS_CXX0X)
-if(COMPILER_SUPPORTS_CXX11)
-       set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=gnu++11")
-elseif(COMPILER_SUPPORTS_CXX0X)
-       set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=gnu++0x")
-else()
-    message(FATAL_ERROR "The compiler ${CMAKE_CXX_COMPILER} has no C++11 support (with GNU extensions). Please use a different C++ compiler.")
-endif()
+set(CMAKE_CXX_STANDARD 11)
+set(CMAKE_CXX_STANDARD_REQUIRED ON)

 # Mark some warnings as errors
 if(CMAKE_CXX_COMPILER_ID STREQUAL "Clang")
 	# Activate as much warnings as possible to avoid errors like
 	# uninitialized variables or other hard to debug bugs.
-	set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wall")
-	set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wno-unknown-warning-option")
-	set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wno-reorder-ctor -Wno-reorder -Wno-pessimizing-move -Wno-unused-variable -Wno-unused-private-field")
+	add_compile_options(
+		-Wall
+		-Wno-unknown-warning-option
+		-Wno-reorder-ctor
+		-Wno-reorder
+		-Wno-pessimizing-move
+		-Wno-unused-variable
+		-Wno-unused-private-field

-	# Make as much warnings considered as errors as possible (only one for now).
-	set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Werror=return-stack-address")
+		# Make as much warnings considered as errors as possible (only one for now).
+		-Werror=return-stack-address)
 endif()

-#Define common directories:
+# Define common directories:
 set(GD_base_dir ${CMAKE_CURRENT_SOURCE_DIR})

-#Add all the CMakeLists:
-ADD_SUBDIRECTORY(ExtLibs)
-IF(BUILD_CORE)
-	ADD_SUBDIRECTORY(Core)
-ENDIF()
-IF(BUILD_GDJS)
-	ADD_SUBDIRECTORY(GDJS)
-ENDIF()
-IF(EMSCRIPTEN)
-	ADD_SUBDIRECTORY(GDevelop.js)
-ENDIF()
-IF(BUILD_EXTENSIONS)
-	ADD_SUBDIRECTORY(Extensions)
-ENDIF()
+# Add all the CMakeLists:
+add_subdirectory(ExtLibs)
+if(BUILD_CORE)
+	add_subdirectory(Core)
+endif()
+if(BUILD_GDJS)
+	add_subdirectory(GDJS)
+endif()
+if(EMSCRIPTEN)
+	add_subdirectory(GDevelop.js)
+endif()
+if(BUILD_EXTENSIONS)
+	add_subdirectory(Extensions)
+endif()
--- a/Core/CMakeLists.txt
+++ b/Core/CMakeLists.txt
@@ -1,83 +1,98 @@
-cmake_minimum_required(VERSION 2.6)
-cmake_policy(SET CMP0015 NEW)
+cmake_minimum_required(VERSION 3.5)

 project(GDCore)

-SET(CMAKE_C_USE_RESPONSE_FILE_FOR_OBJECTS 1) #Force use response file: useful for Ninja build system on Windows.
-SET(CMAKE_CXX_USE_RESPONSE_FILE_FOR_OBJECTS 1)
-SET(CMAKE_C_USE_RESPONSE_FILE_FOR_INCLUDES 1)
-SET(CMAKE_CXX_USE_RESPONSE_FILE_FOR_INCLUDES 1)
+set(CMAKE_C_USE_RESPONSE_FILE_FOR_OBJECTS 1) # Force use response file: useful for Ninja build system on Windows.
+set(CMAKE_CXX_USE_RESPONSE_FILE_FOR_OBJECTS 1)
+set(CMAKE_C_USE_RESPONSE_FILE_FOR_INCLUDES 1)
+set(CMAKE_CXX_USE_RESPONSE_FILE_FOR_INCLUDES 1)

-#Define common directories:
+# Define common directories:
 set(GDCORE_include_dir ${GD_base_dir}/Core PARENT_SCOPE)
 set(GDCORE_lib_dir ${GD_base_dir}/Binaries/Output/${CMAKE_BUILD_TYPE}_${CMAKE_SYSTEM_NAME} PARENT_SCOPE)

-#Dependencies on external libraries:
-###
+# Dependencies on external libraries:
+#

-#Defines
-###
-add_definitions( -DGD_IDE_ONLY )
-IF (EMSCRIPTEN)
-	add_definitions( -DEMSCRIPTEN )
-ENDIF()
-IF(CMAKE_BUILD_TYPE MATCHES "Debug")
-	add_definitions( -DDEBUG )
-ELSE()
-	add_definitions( -DRELEASE )
-ENDIF()
+# Defines
+#
+add_definitions(-DGD_IDE_ONLY)
+if(EMSCRIPTEN)
+	add_definitions(-DEMSCRIPTEN)
+endif()
+if("${CMAKE_BUILD_TYPE}" MATCHES "Debug")
+	add_definitions(-DDEBUG)
+else()
+	add_definitions(-DRELEASE)
+endif()

-IF(WIN32)
-	add_definitions( -DWINDOWS )
-	add_definitions( "-DGD_CORE_API=__declspec(dllexport)" )
-	add_definitions( -D__GNUWIN32__ )
-ELSE()
-    IF(APPLE)
-    add_definitions( -DMACOS )
-    ELSE()
-	add_definitions( -DLINUX )
-	ENDIF()
-	add_definitions( -DGD_API= )
-	add_definitions( -DGD_CORE_API= )
-ENDIF(WIN32)
+if(WIN32)
+	add_definitions(-DWINDOWS)
+	add_definitions("-DGD_CORE_API=__declspec(dllexport)")
+	add_definitions(-D__GNUWIN32__)
+else()
+	if(APPLE)
+		add_definitions(-DMACOS)
+	else()
+		add_definitions(-DLINUX)
+	endif()
+	add_definitions(-DGD_API=)
+	add_definitions(-DGD_CORE_API=)
+endif()

-#The target
-###
+# The target
+#
 include_directories(.)
-file(GLOB_RECURSE source_files GDCore/*)
+file(
+	GLOB_RECURSE
+	source_files
+	GDCore/*)

-file(GLOB_RECURSE formatted_source_files tests/* GDCore/Events/* GDCore/Extensions/* GDCore/IDE/* GDCore/Project/* GDCore/Serialization/* GDCore/Tools/*)
-list(REMOVE_ITEM formatted_source_files "${CMAKE_CURRENT_SOURCE_DIR}/GDCore/IDE/Dialogs/GDCoreDialogs.cpp" "${CMAKE_CURRENT_SOURCE_DIR}/GDCore/IDE/Dialogs/GDCoreDialogs.h" "${CMAKE_CURRENT_SOURCE_DIR}/GDCore/IDE/Dialogs/GDCoreDialogs_dialogs_bitmaps.cpp")
+file(
+	GLOB_RECURSE
+	formatted_source_files
+	tests/*
+	GDCore/Events/*
+	GDCore/Extensions/*
+	GDCore/IDE/*
+	GDCore/Project/*
+	GDCore/Serialization/*
+	GDCore/Tools/*)
+list(
+	REMOVE_ITEM
+	formatted_source_files
+	"${CMAKE_CURRENT_SOURCE_DIR}/GDCore/IDE/Dialogs/GDCoreDialogs.cpp"
+	"${CMAKE_CURRENT_SOURCE_DIR}/GDCore/IDE/Dialogs/GDCoreDialogs.h"
+	"${CMAKE_CURRENT_SOURCE_DIR}/GDCore/IDE/Dialogs/GDCoreDialogs_dialogs_bitmaps.cpp")
 gd_add_clang_utils(GDCore "${formatted_source_files}")

-IF(EMSCRIPTEN)
+if(EMSCRIPTEN)
 	# Emscripten treats all libraries as static libraries
 	add_library(GDCore STATIC ${source_files})
-ELSE()
+else()
 	add_library(GDCore SHARED ${source_files})
-ENDIF()
-IF(EMSCRIPTEN)
+endif()
+if(EMSCRIPTEN)
 	set_target_properties(GDCore PROPERTIES SUFFIX ".bc")
-ELSEIF(WIN32)
+elseif(WIN32)
 	set_target_properties(GDCore PROPERTIES PREFIX "")
-ELSE()
+else()
 	set_target_properties(GDCore PROPERTIES PREFIX "lib")
-ENDIF()
+endif()
 set(LIBRARY_OUTPUT_PATH ${GD_base_dir}/Binaries/Output/${CMAKE_BUILD_TYPE}_${CMAKE_SYSTEM_NAME})
 set(ARCHIVE_OUTPUT_PATH ${GD_base_dir}/Binaries/Output/${CMAKE_BUILD_TYPE}_${CMAKE_SYSTEM_NAME})
 set(RUNTIME_OUTPUT_PATH ${GD_base_dir}/Binaries/Output/${CMAKE_BUILD_TYPE}_${CMAKE_SYSTEM_NAME})

-#Tests
-###
+# Tests
+#
 if(BUILD_TESTS)
 	file(
-	    GLOB_RECURSE
-	    test_source_files
-	    tests/*
-	)
+		GLOB_RECURSE
+		test_source_files
+		tests/*)

 	add_executable(GDCore_tests ${test_source_files})
-	set_target_properties(GDCore_tests PROPERTIES BUILD_WITH_INSTALL_RPATH FALSE) #Allow finding dependencies directly from build path on Mac OS X.
+	set_target_properties(GDCore_tests PROPERTIES BUILD_WITH_INSTALL_RPATH FALSE) # Allow finding dependencies directly from build path on Mac OS X.
 	target_link_libraries(GDCore_tests GDCore)
 	target_link_libraries(GDCore_tests ${CMAKE_DL_LIBS})
 endif()
--- a/Core/GDCore/Events/Builtin/ForEachEvent.cpp
+++ b/Core/GDCore/Events/Builtin/ForEachEvent.cpp
@@ -15,7 +15,7 @@ using namespace std;
 namespace gd {

 ForEachEvent::ForEachEvent()
-    : BaseEvent(), objectsToPick(""), objectsToPickSelected(false) {}
+    : BaseEvent(), objectsToPick("") {}

 vector<gd::InstructionsList*> ForEachEvent::GetAllConditionsVectors() {
  vector<gd::InstructionsList*> allConditions;
--- a/Core/GDCore/Events/Builtin/ForEachEvent.h
+++ b/Core/GDCore/Events/Builtin/ForEachEvent.h
@@ -6,6 +6,8 @@

 #ifndef FOREACHEVENT_H
 #define FOREACHEVENT_H
+#include <vector>
+
 #include "GDCore/Events/Event.h"
 #include "GDCore/Events/EventsList.h"
 namespace gd {
@@ -62,13 +64,17 @@ class GD_CORE_API ForEachEvent : public gd::BaseEvent {
  virtual void UnserializeFrom(gd::Project& project,
                               const SerializerElement& element);

+  std::vector<gd::Expression*> GetAllObjectExpressions() {
+    std::vector<gd::Expression*> allObjectExpressions;
+    allObjectExpressions.push_back(&objectsToPick);
+    return allObjectExpressions;
+  }
+
 private:
  gd::Expression objectsToPick;
  gd::InstructionsList conditions;
  gd::InstructionsList actions;
  gd::EventsList events;
-
-  bool objectsToPickSelected;
 };

 }  // namespace gd
--- a/Core/GDCore/Events/Builtin/LinkEvent.cpp
+++ b/Core/GDCore/Events/Builtin/LinkEvent.cpp
@@ -131,30 +131,36 @@ void LinkEvent::SerializeTo(SerializerElement& element) const {

 void LinkEvent::UnserializeFrom(gd::Project& project,
                                const SerializerElement& element) {
-  SerializerElement& includeElement = element.GetChild("include", 0, "Limites");
-
  SetTarget(element.GetChild("target", 0, "Scene").GetValue().GetString());

-  if (includeElement.HasAttribute("includeAll")) {
-    // Compatibility with GDevelop <= 4.0.92
-    if (includeElement.GetBoolAttribute("includeAll", true)) {
-      SetIncludeAllEvents();
+  // Compatibility with GD <= 5
+  if (element.HasChild("include", "Limites")) {
+    SerializerElement& includeElement = element.GetChild("include", 0, "Limites");
+    if (includeElement.HasAttribute("includeAll")) {
+      // Compatibility with GDevelop <= 4.0.92
+      if (includeElement.GetBoolAttribute("includeAll", true)) {
+        SetIncludeAllEvents();
+      } else {
+        SetIncludeStartAndEnd(includeElement.GetIntAttribute("start"),
+                              includeElement.GetIntAttribute("end"));
+      }
    } else {
-      SetIncludeStartAndEnd(includeElement.GetIntAttribute("start"),
-                            includeElement.GetIntAttribute("end"));
+      // GDevelop > 4.0.92
+      IncludeConfig config = static_cast<IncludeConfig>(
+          includeElement.GetIntAttribute("includeConfig", 0));
+      if (config == INCLUDE_ALL)
+        SetIncludeAllEvents();
+      else if (config == INCLUDE_EVENTS_GROUP)
+        SetIncludeEventsGroup(includeElement.GetStringAttribute("eventsGroup"));
+      else if (config == INCLUDE_BY_INDEX)
+        SetIncludeStartAndEnd(includeElement.GetIntAttribute("start"),
+                              includeElement.GetIntAttribute("end"));
    }
  } else {
-    // GDevelop > 4.0.92
-    IncludeConfig config = static_cast<IncludeConfig>(
-        includeElement.GetIntAttribute("includeConfig", 0));
-    if (config == INCLUDE_ALL)
-      SetIncludeAllEvents();
-    else if (config == INCLUDE_EVENTS_GROUP)
-      SetIncludeEventsGroup(includeElement.GetStringAttribute("eventsGroup"));
-    else if (config == INCLUDE_BY_INDEX)
-      SetIncludeStartAndEnd(includeElement.GetIntAttribute("start"),
-                            includeElement.GetIntAttribute("end"));
+    // Since GDevelop 5, links always include all events.
+    SetIncludeAllEvents();
  }
+  // end of compatibility code
 }

 bool LinkEvent::AcceptVisitor(gd::EventVisitor &eventVisitor) {
--- a/Core/GDCore/Events/CodeGeneration/EffectsCodeGenerator.cpp
+++ b/Core/GDCore/Events/CodeGeneration/EffectsCodeGenerator.cpp
@@ -15,16 +15,48 @@
 #include "GDCore/Project/Layout.h"
 #include "GDCore/Project/Object.h"
 #include "GDCore/Project/Project.h"
+#include "GDCore/IDE/ProjectBrowserHelper.h"

 namespace gd {

-void ExposeProjectEffects(
-    const gd::Project& project,
-    const std::function<void(const gd::Effect& effect)>& worker) {
+void EffectsCodeGenerator::DoVisitObject(gd::Object &object) {
+  auto &effects = object.GetEffects();
+  for (std::size_t e = 0; e < effects.GetEffectsCount(); e++) {
+    auto &effect = effects.GetEffect(e);
+    AddEffectIncludeFiles(effect);
+  }
+};
+
+void EffectsCodeGenerator::AddEffectIncludeFiles(const gd::Effect &effect) {
+  // TODO: this browse all the extensions every time we're trying to find
+  // a new effect. Might be a good idea to rework MetadataProvider to be
+  // faster (not sure if it is a bottleneck at all though - but could be
+  // for events code generation).
+  const gd::EffectMetadata &effectMetadata =
+      MetadataProvider::GetEffectMetadata(platform, effect.GetEffectType());
+
+  for (auto &includeFile : effectMetadata.GetIncludeFiles())
+    includeFiles.insert(includeFile);
+};
+
+void EffectsCodeGenerator::GenerateEffectsIncludeFiles(
+    const gd::Platform &platform,
+    gd::Project &project,
+    std::set<gd::String> &includeFiles) {
+  // TODO Add unit tests on this function.
+  
+  // TODO Merge with UsedExtensionsFinder.
+  // Default lights rely on the fact that UsedExtensionsFinder doesn't find
+  // extension usages for effects. This has the happy side effect of not
+  // including Three.js when no 3D object are in the scenes.
+  // We need to make something explicit to avoid future bugs.
+
  // See also gd::Project::ExposeResources for a method that traverse the whole
  // project (this time for resources) and
  // WholeProjectRefactorer::ExposeProjectEvents.

+  EffectsCodeGenerator effectsCodeGenerator(platform, includeFiles);
+
  // Add layouts effects
  for (std::size_t s = 0; s < project.GetLayoutsCount(); s++) {
    auto& layout = project.GetLayout(s);
@@ -33,47 +65,13 @@ void ExposeProjectEffects(
      auto& effects = layout.GetLayer(l).GetEffects();
      for (std::size_t e = 0; e < effects.GetEffectsCount(); ++e) {
        auto& effect = effects.GetEffect(e);
-        worker(effect);
-      }
-    }
-
-    for (std::size_t i = 0; i < layout.GetObjectsCount(); i++) {
-      auto& object = layout.GetObject(i);
-      auto& effects = object.GetEffects();
-      for (std::size_t e = 0; e < effects.GetEffectsCount(); e++) {
-        auto& effect = effects.GetEffect(e);
-        worker(effect);
+        effectsCodeGenerator.AddEffectIncludeFiles(effect);
      }
    }
  }

-  // Add global object effects
-  for (std::size_t s = 0; s < project.GetObjectsCount(); s++) {
-    auto& effects = project.GetObject(s).GetEffects();
-    for (std::size_t e = 0; e < effects.GetEffectsCount(); e++) {
-      auto& effect = effects.GetEffect(e);
-      worker(effect);
-    }
-  }
-}
-
-void EffectsCodeGenerator::GenerateEffectsIncludeFiles(
-    const gd::Platform& platform,
-    const gd::Project& project,
-    std::set<gd::String>& includeFiles) {
-  ExposeProjectEffects(
-      project, [&platform, &includeFiles](const gd::Effect& effect) {
-        // TODO: this browse all the extensions every time we're trying to find
-        // a new effect. Might be a good idea to rework MetadataProvider to be
-        // faster (not sure if it is a bottleneck at all though - but could be
-        // for events code generation).
-        const gd::EffectMetadata& effectMetadata =
-            MetadataProvider::GetEffectMetadata(platform,
-                                                effect.GetEffectType());
-
-        for (auto& includeFile : effectMetadata.GetIncludeFiles())
-          includeFiles.insert(includeFile);
-      });
+  // Add objects effects
+  gd::ProjectBrowserHelper::ExposeProjectObjects(project, effectsCodeGenerator);
 }

 }  // namespace gd
--- a/Core/GDCore/Events/CodeGeneration/EffectsCodeGenerator.h
+++ b/Core/GDCore/Events/CodeGeneration/EffectsCodeGenerator.h
@@ -3,16 +3,18 @@
 * Copyright 2008-present Florian Rival (Florian.Rival@gmail.com). All rights
 * reserved. This project is released under the MIT License.
 */
-#ifndef GDCORE_EffectsCodeGenerator_H
-#define GDCORE_EffectsCodeGenerator_H
+#pragma once

 #include <set>
 #include <utility>
 #include <vector>
 #include "GDCore/String.h"
+#include "GDCore/IDE/Project/ArbitraryObjectsWorker.h"
+
 namespace gd {
 class Project;
 class Platform;
+class Effect;
 }  // namespace gd

 namespace gd {
@@ -20,16 +22,26 @@ namespace gd {
 /**
 * \brief Internal class used to generate code from events
 */
-class GD_CORE_API EffectsCodeGenerator {
- public:
+class GD_CORE_API EffectsCodeGenerator : public ArbitraryObjectsWorker {
+public:
  /**
   * \brief Add all the include files required by the project effects.
   */
  static void GenerateEffectsIncludeFiles(const gd::Platform& platform,
-                                          const gd::Project& project,
+                                          gd::Project& project,
                                          std::set<gd::String>& includeFiles);
+
+private:
+  EffectsCodeGenerator(const gd::Platform &platform_,
+                       std::set<gd::String> &includeFiles_)
+      : platform(platform_), includeFiles(includeFiles_){};
+
+  void AddEffectIncludeFiles(const gd::Effect& effect);
+
+  void DoVisitObject(gd::Object &object) override;
+
+  const gd::Platform &platform;
+  std::set<gd::String> &includeFiles;
 };

 }  // namespace gd
-
-#endif  // GDCORE_EffectsCodeGenerator_H
--- a/Core/GDCore/Events/CodeGeneration/EventsCodeGenerator.cpp
+++ b/Core/GDCore/Events/CodeGeneration/EventsCodeGenerator.cpp
@@ -267,11 +267,11 @@ gd::String EventsCodeGenerator::GenerateConditionCode(
    return "/* Unknown instruction - skipped. */";
  }

-  AddIncludeFiles(instrInfos.codeExtraInformation.GetIncludeFiles());
+  AddIncludeFiles(instrInfos.GetIncludeFiles());
  maxConditionsListsSize =
      std::max(maxConditionsListsSize, condition.GetSubInstructions().size());

-  if (instrInfos.codeExtraInformation.HasCustomCodeGenerator()) {
+  if (instrInfos.HasCustomCodeGenerator()) {
    context.EnterCustomCondition();
    conditionCode += instrInfos.codeExtraInformation.customCodeGenerator(
        condition, *this, context);
@@ -323,11 +323,6 @@ gd::String EventsCodeGenerator::GenerateConditionCode(
        const ObjectMetadata& objInfo =
            MetadataProvider::GetObjectMetadata(platform, objectType);

-        if (objInfo.IsUnsupportedBaseObjectCapability(
-                instrInfos.GetRequiredBaseObjectCapability())) {
-          conditionCode +=
-              "/* Object with unsupported capability - skipped. */\n";
-        } else {
          AddIncludeFiles(objInfo.includeFiles);
          context.SetCurrentObject(realObjects[i]);
          context.ObjectsListNeeded(realObjects[i]);
@@ -344,7 +339,6 @@ gd::String EventsCodeGenerator::GenerateConditionCode(
                                                   context);

          context.SetNoCurrentObject();
-        }
      }
    }
  } else if (instrInfos.IsBehaviorInstruction()) {
@@ -459,9 +453,9 @@ gd::String EventsCodeGenerator::GenerateActionCode(
    return "/* Unknown instruction - skipped. */";
  }

-  AddIncludeFiles(instrInfos.codeExtraInformation.GetIncludeFiles());
+  AddIncludeFiles(instrInfos.GetIncludeFiles());

-  if (instrInfos.codeExtraInformation.HasCustomCodeGenerator()) {
+  if (instrInfos.HasCustomCodeGenerator()) {
    return instrInfos.codeExtraInformation.customCodeGenerator(
        action, *this, context);
  }
@@ -515,10 +509,6 @@ gd::String EventsCodeGenerator::GenerateActionCode(
        const ObjectMetadata& objInfo =
            MetadataProvider::GetObjectMetadata(platform, objectType);

-        if (objInfo.IsUnsupportedBaseObjectCapability(
-                instrInfos.GetRequiredBaseObjectCapability())) {
-          actionCode += "/* Object with unsupported capability - skipped. */\n";
-        } else {
          AddIncludeFiles(objInfo.includeFiles);
          context.SetCurrentObject(realObjects[i]);
          context.ObjectsListNeeded(realObjects[i]);
@@ -535,7 +525,6 @@ gd::String EventsCodeGenerator::GenerateActionCode(
                                             optionalAsyncCallbackName);

          context.SetNoCurrentObject();
-        }
      }
    }
  } else if (instrInfos.IsBehaviorInstruction()) {
@@ -974,6 +963,8 @@ void EventsCodeGenerator::DeleteUselessEvents(gd::EventsList& events) {
 */
 void EventsCodeGenerator::PreprocessEventList(gd::EventsList& listEvent) {
  for (std::size_t i = 0; i < listEvent.GetEventsCount(); ++i) {
+    if (listEvent[i].IsDisabled()) continue;
+
    listEvent[i].Preprocess(*this, listEvent, i);
    if (i <
        listEvent.GetEventsCount()) {  // Be sure that that there is still an
@@ -1019,15 +1010,15 @@ gd::String EventsCodeGenerator::GenerateFreeCondition(
    bool conditionInverted,
    gd::EventsCodeGenerationContext& context) {
  // Generate call
-  gd::String predicat;
+  gd::String predicate;
  if (instrInfos.codeExtraInformation.type == "number" ||
      instrInfos.codeExtraInformation.type == "string") {
-    predicat = GenerateRelationalOperatorCall(
+    predicate = GenerateRelationalOperatorCall(
        instrInfos,
        arguments,
        instrInfos.codeExtraInformation.functionCallName);
  } else {
-    predicat = instrInfos.codeExtraInformation.functionCallName + "(" +
+    predicate = instrInfos.codeExtraInformation.functionCallName + "(" +
               GenerateArgumentsList(arguments, 0) + ")";
  }

@@ -1040,10 +1031,10 @@ gd::String EventsCodeGenerator::GenerateFreeCondition(
      conditionAlreadyTakeCareOfInversion = true;
  }
  if (!conditionAlreadyTakeCareOfInversion && conditionInverted)
-    predicat = GenerateNegatedPredicat(predicat);
+    predicate = GenerateNegatedPredicate(predicate);

  // Generate condition code
-  return returnBoolean + " = " + predicat + ";\n";
+  return returnBoolean + " = " + predicate + ";\n";
 }

 gd::String EventsCodeGenerator::GenerateObjectCondition(
@@ -1065,18 +1056,18 @@ gd::String EventsCodeGenerator::GenerateObjectCondition(
                instrInfos.codeExtraInformation.functionCallName;

  // Create call
-  gd::String predicat;
+  gd::String predicate;
  if ((instrInfos.codeExtraInformation.type == "number" ||
       instrInfos.codeExtraInformation.type == "string")) {
-    predicat = GenerateRelationalOperatorCall(
+    predicate = GenerateRelationalOperatorCall(
        instrInfos, arguments, objectFunctionCallNamePart, 1);
  } else {
-    predicat = objectFunctionCallNamePart + "(" +
+    predicate = objectFunctionCallNamePart + "(" +
               GenerateArgumentsList(arguments, 1) + ")";
  }
-  if (conditionInverted) predicat = GenerateNegatedPredicat(predicat);
+  if (conditionInverted) predicate = GenerateNegatedPredicate(predicate);

-  return "For each picked object \"" + objectName + "\", check " + predicat +
+  return "For each picked object \"" + objectName + "\", check " + predicate +
         ".\n";
 }

@@ -1090,16 +1081,16 @@ gd::String EventsCodeGenerator::GenerateBehaviorCondition(
    bool conditionInverted,
    gd::EventsCodeGenerationContext& context) {
  // Create call
-  gd::String predicat;
+  gd::String predicate;
  if ((instrInfos.codeExtraInformation.type == "number" ||
       instrInfos.codeExtraInformation.type == "string")) {
-    predicat = GenerateRelationalOperatorCall(instrInfos, arguments, "", 2);
+    predicate = GenerateRelationalOperatorCall(instrInfos, arguments, "", 2);
  } else {
-    predicat = "(" + GenerateArgumentsList(arguments, 2) + ")";
+    predicate = "(" + GenerateArgumentsList(arguments, 2) + ")";
  }
-  if (conditionInverted) predicat = GenerateNegatedPredicat(predicat);
+  if (conditionInverted) predicate = GenerateNegatedPredicate(predicate);

-  return "For each picked object \"" + objectName + "\", check " + predicat +
+  return "For each picked object \"" + objectName + "\", check " + predicate +
         " for behavior \"" + behaviorName + "\".\n";
 }

--- a/Core/GDCore/Events/CodeGeneration/EventsCodeGenerator.h
+++ b/Core/GDCore/Events/CodeGeneration/EventsCodeGenerator.h
@@ -668,13 +668,13 @@ class GD_CORE_API EventsCodeGenerator {
  };

  /**
-   * \brief Must negate a predicat.
+   * \brief Must negate a predicate.
   *
-   * The default implementation generates C-style code : It wraps the predicat
+   * The default implementation generates C-style code : It wraps the predicate
   * inside parenthesis and add a !.
   */
-  virtual gd::String GenerateNegatedPredicat(const gd::String& predicat) const {
-    return "!(" + predicat + ")";
+  virtual gd::String GenerateNegatedPredicate(const gd::String& predicate) const {
+    return "!(" + predicate + ")";
  };

  virtual gd::String GenerateFreeCondition(
--- a/Core/GDCore/Events/CodeGeneration/ExpressionCodeGenerator.cpp
+++ b/Core/GDCore/Events/CodeGeneration/ExpressionCodeGenerator.cpp
@@ -216,10 +216,10 @@ gd::String ExpressionCodeGenerator::GenerateFreeFunctionCode(
    const std::vector<std::unique_ptr<ExpressionNode>>& parameters,
    const ExpressionMetadata& expressionMetadata) {
  codeGenerator.AddIncludeFiles(
-      expressionMetadata.codeExtraInformation.GetIncludeFiles());
+      expressionMetadata.GetIncludeFiles());

  // Launch custom code generator if needed
-  if (expressionMetadata.codeExtraInformation.HasCustomCodeGenerator()) {
+  if (expressionMetadata.HasCustomCodeGenerator()) {
    return expressionMetadata.codeExtraInformation.customCodeGenerator(
        PrintParameters(parameters), codeGenerator, context);
  }
@@ -242,10 +242,10 @@ gd::String ExpressionCodeGenerator::GenerateObjectFunctionCode(
      codeGenerator.GetObjectsAndGroups();

  codeGenerator.AddIncludeFiles(
-      expressionMetadata.codeExtraInformation.GetIncludeFiles());
+      expressionMetadata.GetIncludeFiles());

  // Launch custom code generator if needed
-  if (expressionMetadata.codeExtraInformation.HasCustomCodeGenerator()) {
+  if (expressionMetadata.HasCustomCodeGenerator()) {
    return expressionMetadata.codeExtraInformation.customCodeGenerator(
        PrintParameters(parameters), codeGenerator, context);
  }
@@ -270,11 +270,6 @@ gd::String ExpressionCodeGenerator::GenerateObjectFunctionCode(
    const ObjectMetadata& objInfo = MetadataProvider::GetObjectMetadata(
        codeGenerator.GetPlatform(), objectType);

-    if (objInfo.IsUnsupportedBaseObjectCapability(
-            expressionMetadata.GetRequiredBaseObjectCapability())) {
-      // Do nothing, skipping objects not supporting the capability required by
-      // this expression.
-    } else {
      codeGenerator.AddIncludeFiles(objInfo.includeFiles);
      functionOutput = codeGenerator.GenerateObjectFunctionCall(
          realObjects[i],
@@ -283,7 +278,6 @@ gd::String ExpressionCodeGenerator::GenerateObjectFunctionCode(
          parametersCode,
          functionOutput,
          context);
-    }
  }

  return functionOutput;
@@ -300,10 +294,10 @@ gd::String ExpressionCodeGenerator::GenerateBehaviorFunctionCode(
      codeGenerator.GetObjectsAndGroups();

  codeGenerator.AddIncludeFiles(
-      expressionMetadata.codeExtraInformation.GetIncludeFiles());
+      expressionMetadata.GetIncludeFiles());

  // Launch custom code generator if needed
-  if (expressionMetadata.codeExtraInformation.HasCustomCodeGenerator()) {
+  if (expressionMetadata.HasCustomCodeGenerator()) {
    return expressionMetadata.codeExtraInformation.customCodeGenerator(
        PrintParameters(parameters), codeGenerator, context);
  }
--- a/Core/GDCore/Events/Event.h
+++ b/Core/GDCore/Events/Event.h
@@ -282,6 +282,14 @@ class GD_CORE_API BaseEvent {
   */
  bool IsFolded() const { return folded; }

+  /**
+   * \brief Return a list of all objects linked to the event.
+   */
+  virtual std::vector<gd::Expression*> GetAllObjectExpressions() {
+    std::vector<gd::Expression*> allObjectExpressions;
+    return allObjectExpressions;
+  }
+
  ///@}

  std::weak_ptr<gd::BaseEvent>
--- a/Core/GDCore/Events/Parsers/ExpressionParser2.cpp
+++ b/Core/GDCore/Events/Parsers/ExpressionParser2.cpp
@@ -19,8 +19,10 @@
 #include "GDCore/Project/Project.h"
 #include "GDCore/Tools/Localization.h"
 #include "GDCore/Tools/MakeUnique.h"
+#include "GrammarTerminals.h"

 using namespace std;
+using namespace gd::GrammarTerminals;

 namespace gd {

--- a/Core/GDCore/Events/Parsers/ExpressionParser2.h
+++ b/Core/GDCore/Events/Parsers/ExpressionParser2.h
@@ -18,6 +18,7 @@
 #include "GDCore/String.h"
 #include "GDCore/Tools/Localization.h"
 #include "GDCore/Tools/MakeUnique.h"
+#include "GrammarTerminals.h"
 namespace gd {
 class Expression;
 class ObjectsContainer;
@@ -28,6 +29,8 @@ class ExpressionMetadata;

 namespace gd {

+using namespace gd::GrammarTerminals;
+
 /** \brief Parse an expression, returning a tree of node corresponding
 * to the parsed expression.
 *
@@ -211,7 +214,7 @@ class GD_CORE_API ExpressionParser2 {
      }
      SkipIfChar(IsClosingParenthesis);
      return factor;
-    } else if (IsIdentifierAllowedChar()) {
+    } else if (CheckIfChar(IsAllowedInIdentifier)) {
      return Identifier();
    }

@@ -606,95 +609,6 @@ class GD_CORE_API ExpressionParser2 {
    return predicate(character);
  }

-  bool IsIdentifierAllowedChar() {
-    if (currentPosition >= expression.size()) return false;
-    gd::String::value_type character = expression[currentPosition];
-
-    // Quickly compare if the character is a number or ASCII character.
-    if ((character >= '0' && character <= '9') ||
-        (character >= 'A' && character <= 'Z') ||
-        (character >= 'a' && character <= 'z'))
-      return true;
-
-    // Otherwise do the full check against separators forbidden in identifiers.
-    if (!IsParameterSeparator(character) && !IsDot(character) &&
-        !IsQuote(character) && !IsBracket(character) &&
-        !IsExpressionOperator(character) && !IsTermOperator(character)) {
-      return true;
-    }
-
-    return false;
-  }
-
-  static bool IsWhitespace(gd::String::value_type character) {
-    return character == ' ' || character == '\n' || character == '\r';
-  }
-
-  static bool IsParameterSeparator(gd::String::value_type character) {
-    return character == ',';
-  }
-
-  static bool IsDot(gd::String::value_type character) {
-    return character == '.';
-  }
-
-  static bool IsQuote(gd::String::value_type character) {
-    return character == '"';
-  }
-
-  static bool IsBracket(gd::String::value_type character) {
-    return character == '(' || character == ')' || character == '[' ||
-           character == ']' || character == '{' || character == '}';
-  }
-
-  static bool IsOpeningParenthesis(gd::String::value_type character) {
-    return character == '(';
-  }
-
-  static bool IsClosingParenthesis(gd::String::value_type character) {
-    return character == ')';
-  }
-
-  static bool IsOpeningSquareBracket(gd::String::value_type character) {
-    return character == '[';
-  }
-
-  static bool IsClosingSquareBracket(gd::String::value_type character) {
-    return character == ']';
-  }
-
-  static bool IsExpressionEndingChar(gd::String::value_type character) {
-    return character == ',' || IsClosingParenthesis(character) ||
-           IsClosingSquareBracket(character);
-  }
-
-  static bool IsExpressionOperator(gd::String::value_type character) {
-    return character == '+' || character == '-' || character == '<' ||
-           character == '>' || character == '?' || character == '^' ||
-           character == '=' || character == '\\' || character == ':' ||
-           character == '!';
-  }
-
-  static bool IsUnaryOperator(gd::String::value_type character) {
-    return character == '+' || character == '-';
-  }
-
-  static bool IsTermOperator(gd::String::value_type character) {
-    return character == '/' || character == '*';
-  }
-
-  static bool IsNumberFirstChar(gd::String::value_type character) {
-    return character == '.' || (character >= '0' && character <= '9');
-  }
-
-  static bool IsNonZeroDigit(gd::String::value_type character) {
-    return (character >= '1' && character <= '9');
-  }
-
-  static bool IsZeroDigit(gd::String::value_type character) {
-    return character == '0';
-  }
-
  bool IsNamespaceSeparator() {
    // Namespace separator is a special kind of delimiter as it is 2 characters
    // long
@@ -715,7 +629,7 @@ class GD_CORE_API ExpressionParser2 {
    gd::String name;
    size_t startPosition = currentPosition;
    while (currentPosition < expression.size() &&
-           (IsIdentifierAllowedChar()
+           (CheckIfChar(IsAllowedInIdentifier)
            // Allow whitespace in identifier name for compatibility
            || expression[currentPosition] == ' ')) {
      name += expression[currentPosition];
--- a/Core/GDCore/Events/Parsers/GrammarTerminals.h
+++ b/Core/GDCore/Events/Parsers/GrammarTerminals.h
@@ -0,0 +1,107 @@
+#pragma once
+#include "GDCore/String.h"
+
+namespace gd {
+
+/**
+ * Contains functions to handle the grammar of the expressions accepted by GDevelop.
+ */
+namespace GrammarTerminals {
+
+inline bool IsWhitespace(gd::String::value_type character) {
+  return character == ' ' || character == '\n' || character == '\r';
+}
+
+inline bool IsParameterSeparator(gd::String::value_type character) {
+  return character == ',';
+}
+
+inline bool IsDot(gd::String::value_type character) { return character == '.'; }
+
+inline bool IsQuote(gd::String::value_type character) {
+  return character == '"';
+}
+
+inline bool IsBracket(gd::String::value_type character) {
+  return character == '(' || character == ')' || character == '[' ||
+         character == ']' || character == '{' || character == '}';
+}
+
+inline bool IsOpeningParenthesis(gd::String::value_type character) {
+  return character == '(';
+}
+
+inline bool IsClosingParenthesis(gd::String::value_type character) {
+  return character == ')';
+}
+
+inline bool IsOpeningSquareBracket(gd::String::value_type character) {
+  return character == '[';
+}
+
+inline bool IsClosingSquareBracket(gd::String::value_type character) {
+  return character == ']';
+}
+
+inline bool IsExpressionEndingChar(gd::String::value_type character) {
+  return character == ',' || IsClosingParenthesis(character) ||
+         IsClosingSquareBracket(character);
+}
+
+inline bool IsExpressionOperator(gd::String::value_type character) {
+  return character == '+' || character == '-' || character == '<' ||
+         character == '>' || character == '?' || character == '^' ||
+         character == '=' || character == '\\' || character == ':' ||
+         character == '!';
+}
+
+inline bool IsUnaryOperator(gd::String::value_type character) {
+  return character == '+' || character == '-';
+}
+
+inline bool IsTermOperator(gd::String::value_type character) {
+  return character == '/' || character == '*';
+}
+
+inline bool IsNumberFirstChar(gd::String::value_type character) {
+  return character == '.' || (character >= '0' && character <= '9');
+}
+
+inline bool IsNonZeroDigit(gd::String::value_type character) {
+  return (character >= '1' && character <= '9');
+}
+
+inline bool IsZeroDigit(gd::String::value_type character) {
+  return character == '0';
+}
+
+/**
+ * Check if the given character can be used in an identifier. This is
+ * any unicode character, except for:
+ * `, . " () [] {} + - < > ? ^ = \ : ! / *` and whitespaces (space, line break, carriage return).
+ *
+ * This is loosely based on what is allowed in languages like JavaScript
+ * (see https://mathiasbynens.be/notes/javascript-properties), without support
+ * for unicode escape syntax, and allowing all unicode ranges. The only
+ * disallowed characters are the one used for the grammar.
+ */
+inline bool IsAllowedInIdentifier(gd::String::value_type character) {
+  // Quickly compare if the character is a number or ASCII character.
+  if ((character >= '0' && character <= '9') ||
+      (character >= 'A' && character <= 'Z') ||
+      (character >= 'a' && character <= 'z'))
+    return true;
+
+  // Otherwise do the full check against separators forbidden in identifiers.
+  if (!IsParameterSeparator(character) && !IsDot(character) &&
+      !IsQuote(character) && !IsBracket(character) &&
+      !IsExpressionOperator(character) && !IsTermOperator(character) &&
+      !IsWhitespace(character)) {
+    return true;
+  }
+
+  return false;
+}
+
+}  // namespace GrammarTerminals
+}  // namespace gd
--- a/Core/GDCore/Events/Tools/EventsCodeNameMangler.cpp
+++ b/Core/GDCore/Events/Tools/EventsCodeNameMangler.cpp
@@ -17,7 +17,7 @@ const gd::String& EventsCodeNameMangler::GetMangledObjectsListName(
    return it->second;
  }

-  gd::String partiallyMangledName = originalObjectName;
+  gd::String partiallyMangledName = GetMangledNameWithForbiddenUnderscore(originalObjectName);
  static const gd::String allowedCharacters =
      "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789";

@@ -43,7 +43,15 @@ const gd::String& EventsCodeNameMangler::GetExternalEventsFunctionMangledName(
    return it->second;
  }

-  gd::String partiallyMangledName = externalEventsName;
+  gd::String partiallyMangledName = GetMangledNameWithForbiddenUnderscore(externalEventsName);
+
+  mangledExternalEventsNames[externalEventsName] = "GDExternalEvents" + partiallyMangledName;
+  return mangledExternalEventsNames[externalEventsName];
+}
+
+gd::String EventsCodeNameMangler::GetMangledNameWithForbiddenUnderscore(
+    const gd::String &name) {
+  gd::String partiallyMangledName = name;
  static const gd::String allowedCharacters =
      "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789";

@@ -57,11 +65,30 @@ const gd::String& EventsCodeNameMangler::GetExternalEventsFunctionMangledName(
      partiallyMangledName.replace(i, 1, "_" + gd::String::From(unallowedChar));
    }
  }
-
-  mangledExternalEventsNames[externalEventsName] = "GDExternalEvents" + partiallyMangledName;
-  return mangledExternalEventsNames[externalEventsName];
+  return partiallyMangledName;
 }

+gd::String EventsCodeNameMangler::GetMangledName(
+    const gd::String &name) {
+  gd::String partiallyMangledName = name;
+  static const gd::String allowedCharacters =
+      "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789_";
+
+  for (size_t i = 0; i < partiallyMangledName.size();
+       ++i)  // Replace all unallowed letter by an underscore and the ascii
+             // number of the letter
+  {
+    if (allowedCharacters.find_first_of(
+            std::u32string(1, partiallyMangledName[i])) == gd::String::npos) {
+      char32_t unallowedChar = partiallyMangledName[i];
+      partiallyMangledName.replace(i, 1, "_" + gd::String::From(unallowedChar));
+    }
+  }
+  return partiallyMangledName;
+}
+
+
+
 const gd::String& ManObjListName(const gd::String &objectName) {
  return EventsCodeNameMangler::Get()->GetMangledObjectsListName(objectName);
 }
--- a/Core/GDCore/Events/Tools/EventsCodeNameMangler.h
+++ b/Core/GDCore/Events/Tools/EventsCodeNameMangler.h
@@ -36,6 +36,8 @@ class GD_CORE_API EventsCodeNameMangler {
  const gd::String &GetExternalEventsFunctionMangledName(
      const gd::String &externalEventsName);

+  static gd::String GetMangledName(const gd::String &name);
+
  static EventsCodeNameMangler *Get();
  static void DestroySingleton();

@@ -44,6 +46,9 @@ class GD_CORE_API EventsCodeNameMangler {
  virtual ~EventsCodeNameMangler(){};
  static EventsCodeNameMangler *_singleton;

+  // This method is inlined to avoid to copy the returned string.
+  static inline gd::String GetMangledNameWithForbiddenUnderscore(const gd::String &name);
+
  std::unordered_map<gd::String, gd::String>
      mangledObjectNames;  ///< Memoized results of mangling for objects
  std::unordered_map<gd::String, gd::String>
--- a/Core/GDCore/Extensions/Builtin/AllBuiltinExtensions.h
+++ b/Core/GDCore/Extensions/Builtin/AllBuiltinExtensions.h
@@ -43,6 +43,12 @@ class GD_CORE_API BuiltinExtensionsImplementer {
  static void ImplementsVariablesExtension(gd::PlatformExtension& extension);
  static void ImplementsWindowExtension(gd::PlatformExtension& extension);
  static void ImplementsAsyncExtension(gd::PlatformExtension& extension);
+  static void ImplementsResizableExtension(gd::PlatformExtension& extension);
+  static void ImplementsScalableExtension(gd::PlatformExtension& extension);
+  static void ImplementsFlippableExtension(gd::PlatformExtension& extension);
+  static void ImplementsAnimatableExtension(gd::PlatformExtension& extension);
+  static void ImplementsEffectExtension(gd::PlatformExtension& extension);
+  static void ImplementsOpacityExtension(gd::PlatformExtension& extension);
 };

 }  // namespace gd
--- a/Core/GDCore/Extensions/Builtin/BaseObjectExtension.cpp
+++ b/Core/GDCore/Extensions/Builtin/BaseObjectExtension.cpp
@@ -29,8 +29,16 @@ void GD_CORE_API BuiltinExtensionsImplementer::ImplementsBaseObjectExtension(
      .SetIcon("res/actions/force24.png");
  extension.AddInstructionOrExpressionGroupMetadata(_("Variables"))
      .SetIcon("res/conditions/var24.png");
+  extension.AddInstructionOrExpressionGroupMetadata(_("Timers"))
+      .SetIcon("res/actions/timer24.png");
+  extension.AddInstructionOrExpressionGroupMetadata(_("Visibility"))
+      .SetIcon("res/actions/visibilite24.png");
  extension.AddInstructionOrExpressionGroupMetadata(_("Position"))
      .SetIcon("res/actions/position24_black.png");
+  extension.AddInstructionOrExpressionGroupMetadata(_("Angle"))
+      .SetIcon("res/actions/direction24_black.png");
+  extension.AddInstructionOrExpressionGroupMetadata(_("Size"))
+      .SetIcon("res/actions/scale24_black.png");

  gd::ObjectMetadata& obj = extension.AddObject<gd::ObjectConfiguration>(
      "", _("Base object"), _("Base object"), "res/objeticon24.png");
@@ -1101,6 +1109,7 @@ void GD_CORE_API BuiltinExtensionsImplementer::ImplementsBaseObjectExtension(
                    "res/actions/scaleWidth_black.png")
      .AddParameter("object", _("Object"));

+  // Deprecated
  obj.AddExpression("Largeur",
                    _("Width"),
                    _("Width of the object"),
@@ -1116,6 +1125,7 @@ void GD_CORE_API BuiltinExtensionsImplementer::ImplementsBaseObjectExtension(
                    "res/actions/scaleHeight_black.png")
      .AddParameter("object", _("Object"));

+  // Deprecated
  obj.AddExpression("Hauteur",
                    _("Height"),
                    _("Height of the object"),
@@ -1201,7 +1211,7 @@ void GD_CORE_API BuiltinExtensionsImplementer::ImplementsBaseObjectExtension(
  obj.AddExpression("ObjectTimerElapsedTime",
                    _("Object timer value"),
                    _("Value of an object timer"),
-                    _("Object timers"),
+                    _("Timers"),
                    "res/actions/time.png")
      .AddParameter("object", _("Object"))
      .AddParameter("identifier", _("Timer's name"), "objectTimer");
@@ -1251,6 +1261,7 @@ void GD_CORE_API BuiltinExtensionsImplementer::ImplementsBaseObjectExtension(
      .AddParameter("expression", _("Target X position"))
      .AddParameter("expression", _("Target Y position"));

+  // Deprecated
  obj.AddAction("EnableEffect",
                _("Enable an object effect"),
                _("Enable an effect on the object"),
@@ -1262,8 +1273,9 @@ void GD_CORE_API BuiltinExtensionsImplementer::ImplementsBaseObjectExtension(
      .AddParameter("objectEffectName", _("Effect name"))
      .AddParameter("yesorno", _("Enable?"))
      .MarkAsSimple()
-      .SetRequiresBaseObjectCapability("effect");
+      .SetHidden();

+  // Deprecated
  obj.AddAction("SetEffectDoubleParameter",
                _("Effect parameter (number)"),
                _("Change the value of a parameter of an effect.") + "\n" +
@@ -1278,8 +1290,9 @@ void GD_CORE_API BuiltinExtensionsImplementer::ImplementsBaseObjectExtension(
      .AddParameter("objectEffectParameterName", _("Parameter name"))
      .AddParameter("expression", _("New value"))
      .MarkAsSimple()
-      .SetRequiresBaseObjectCapability("effect");
+      .SetHidden();

+  // Deprecated
  obj.AddAction("SetEffectStringParameter",
                _("Effect parameter (string)"),
                _("Change the value (string) of a parameter of an effect.") +
@@ -1295,8 +1308,9 @@ void GD_CORE_API BuiltinExtensionsImplementer::ImplementsBaseObjectExtension(
      .AddParameter("objectEffectParameterName", _("Parameter name"))
      .AddParameter("string", _("New value"))
      .MarkAsSimple()
-      .SetRequiresBaseObjectCapability("effect");
+      .SetHidden();

+  // Deprecated
  obj.AddAction("SetEffectBooleanParameter",
                _("Effect parameter (enable or disable)"),
                _("Enable or disable a parameter of an effect.") + "\n" +
@@ -1311,8 +1325,9 @@ void GD_CORE_API BuiltinExtensionsImplementer::ImplementsBaseObjectExtension(
      .AddParameter("objectEffectParameterName", _("Parameter name"))
      .AddParameter("yesorno", _("Enable?"))
      .MarkAsSimple()
-      .SetRequiresBaseObjectCapability("effect");
+      .SetHidden();

+  // Deprecated
  obj.AddCondition("IsEffectEnabled",
                   _("Effect is enabled"),
                   _("Check if the effect on an object is enabled."),
@@ -1323,7 +1338,7 @@ void GD_CORE_API BuiltinExtensionsImplementer::ImplementsBaseObjectExtension(
      .AddParameter("object", _("Object"))
      .AddParameter("objectEffectName", _("Effect name"))
      .MarkAsSimple()
-      .SetRequiresBaseObjectCapability("effect");
+      .SetHidden();

  obj.AddAction("SetIncludedInParentCollisionMask",
                _("Include in parent collision mask"),
--- a/Core/GDCore/Extensions/Builtin/Capabilities/AnimatableExtension.cpp
+++ b/Core/GDCore/Extensions/Builtin/Capabilities/AnimatableExtension.cpp
@@ -0,0 +1,135 @@
+/*
+ * GDevelop Core
+ * Copyright 2008-2016 Florian Rival (Florian.Rival@gmail.com). All rights
+ * reserved. This project is released under the GNU Lesser General Public
+ * License.
+ */
+#include "GDCore/Extensions/Builtin/AllBuiltinExtensions.h"
+#include "GDCore/Extensions/Metadata/MultipleInstructionMetadata.h"
+#include "GDCore/Project/Behavior.h"
+#include "GDCore/Project/BehaviorsSharedData.h"
+#include "GDCore/Project/Object.h"
+#include "GDCore/Tools/Localization.h"
+
+using namespace std;
+namespace gd {
+
+void GD_CORE_API BuiltinExtensionsImplementer::ImplementsAnimatableExtension(
+    gd::PlatformExtension& extension) {
+  extension
+      .SetExtensionInformation("AnimatableCapability",
+                               _("Animatable capability"),
+                               _("Animate objects."),
+                               "Florian Rival",
+                               "Open source (MIT License)")
+      .SetExtensionHelpPath("/objects");
+  extension.AddInstructionOrExpressionGroupMetadata(_("Animations and images"))
+      .SetIcon("res/actions/animation24.png");
+
+  gd::BehaviorMetadata& aut = extension.AddBehavior(
+      "AnimatableBehavior",
+      _("Animatable capability"),
+      "Animation",
+      _("Animate objects."),
+      "",
+      "res/actions/animation24.png",
+      "AnimatableBehavior",
+      std::make_shared<gd::Behavior>(),
+      std::make_shared<gd::BehaviorsSharedData>())
+    .SetHidden();
+
+  aut.AddExpressionAndConditionAndAction(
+         "number",
+         "Index",
+         _("Animation (by number)"),
+         _("the number of the animation played by the object (the number from "
+           "the animations list)"),
+         _("the number of the animation"),
+         _("Animations and images"),
+         "res/actions/animation24.png")
+      .AddParameter("object", _("Object"))
+      .AddParameter("behavior", _("Behavior"), "AnimatableBehavior")
+      .UseStandardParameters(
+          "number", gd::ParameterOptions::MakeNewOptions().SetDescription(
+                        _("Animation index")))
+      .MarkAsSimple();
+
+  aut.AddExpressionAndConditionAndAction(
+         "string",
+         "Name",
+         _("Animation (by name)"),
+         _("the animation played by the object using the name of the "
+           "animation."),
+         _("the animation"),
+         _("Animations and images"),
+         "res/actions/animation24.png")
+      .AddParameter("object", _("Object"))
+      .AddParameter("behavior", _("Behavior"), "AnimatableBehavior")
+      .UseStandardParameters(
+          "objectAnimationName", gd::ParameterOptions::MakeNewOptions().SetDescription(
+                        _("Animation name")))
+      .MarkAsSimple();
+
+  aut.AddScopedAction("PauseAnimation",
+                _("Pause the animation"),
+                _("Pause the animation of the object"),
+                _("Pause the animation of _PARAM0_"),
+                _("Animations and images"),
+                "res/actions/animation24.png",
+                "res/actions/animation.png")
+      .AddParameter("object", _("Object"))
+      .AddParameter("behavior", _("Behavior"), "AnimatableBehavior")
+      .MarkAsSimple();
+
+  aut.AddScopedAction("PlayAnimation",
+                _("Resume the animation"),
+                _("Resume the animation of the object"),
+                _("Resume the animation of _PARAM0_"),
+                _("Animations and images"),
+                "res/actions/animation24.png",
+                "res/actions/animation.png")
+      .AddParameter("object", _("Object"))
+      .AddParameter("behavior", _("Behavior"), "AnimatableBehavior")
+      .MarkAsSimple();
+
+  aut.AddExpressionAndConditionAndAction(
+         "number",
+         "SpeedScale",
+         _("Animation speed scale"),
+         _("the animation speed scale (1 = the default speed, >1 = faster and "
+           "<1 = slower)"),
+         _("the animation speed scale"),
+         _("Animations and images"),
+         "res/actions/animation24.png")
+      .AddParameter("object", _("Object"))
+      .AddParameter("behavior", _("Behavior"), "AnimatableBehavior")
+      .UseStandardParameters(
+          "number", gd::ParameterOptions::MakeNewOptions().SetDescription(
+                        _("Speed scale")))
+      .MarkAsSimple();
+
+  aut.AddScopedCondition("IsAnimationPaused",
+                   _("Animation paused"),
+                   _("Check if the animation of an object is paused."),
+                   _("The animation of _PARAM0_ is paused"),
+                   _("Animations and images"),
+                   "res/conditions/animation24.png",
+                   "res/conditions/animation.png")
+      .AddParameter("object", _("Object"))
+      .AddParameter("behavior", _("Behavior"), "AnimatableBehavior")
+      .MarkAsSimple();
+
+  aut.AddScopedCondition("HasAnimationEnded",
+                   _("Animation finished"),
+                   _("Check if the animation being played by the Sprite object "
+                     "is finished."),
+                   _("The animation of _PARAM0_ is finished"),
+                   _("Animations and images"),
+                   "res/conditions/animation24.png",
+                   "res/conditions/animation.png")
+      .AddParameter("object", _("Object"))
+      .AddParameter("behavior", _("Behavior"), "AnimatableBehavior")
+      .MarkAsSimple();
+}
+
+}  // namespace gd
--- a/Core/GDCore/Extensions/Builtin/Capabilities/EffectExtension.cpp
+++ b/Core/GDCore/Extensions/Builtin/Capabilities/EffectExtension.cpp
@@ -0,0 +1,116 @@
+/*
+ * GDevelop Core
+ * Copyright 2008-2016 Florian Rival (Florian.Rival@gmail.com). All rights
+ * reserved. This project is released under the GNU Lesser General Public
+ * License.
+ */
+#include "GDCore/Extensions/Builtin/AllBuiltinExtensions.h"
+#include "GDCore/Extensions/Metadata/MultipleInstructionMetadata.h"
+#include "GDCore/Project/Behavior.h"
+#include "GDCore/Project/BehaviorsSharedData.h"
+#include "GDCore/Project/Object.h"
+#include "GDCore/Tools/Localization.h"
+
+using namespace std;
+namespace gd {
+
+void GD_CORE_API BuiltinExtensionsImplementer::ImplementsEffectExtension(
+    gd::PlatformExtension& extension) {
+  extension
+      .SetExtensionInformation("EffectCapability",
+                               _("Effect capability"),
+                               _("Apply visual effects to objects."),
+                               "Florian Rival",
+                               "Open source (MIT License)")
+      .SetExtensionHelpPath("/objects");
+  extension.AddInstructionOrExpressionGroupMetadata(_("Effects"))
+      .SetIcon("res/actions/effect24.png");
+
+  gd::BehaviorMetadata& aut = extension.AddBehavior(
+      "EffectBehavior",
+      _("Effect capability"),
+      "Effect",
+      _("Apply visual effects to objects."),
+      "",
+      "res/actions/effect24.png",
+      "EffectBehavior",
+      std::make_shared<gd::Behavior>(),
+      std::make_shared<gd::BehaviorsSharedData>())
+    .SetHidden();
+
+  aut.AddScopedAction("EnableEffect",
+                _("Enable an object effect"),
+                _("Enable an effect on the object"),
+                _("Enable effect _PARAM2_ on _PARAM0_: _PARAM3_"),
+                _("Effects"),
+                "res/actions/effect24.png",
+                "res/actions/effect.png")
+      .AddParameter("object", _("Object"))
+      .AddParameter("behavior", _("Behavior"), "EffectBehavior")
+      .AddParameter("objectEffectName", _("Effect name"))
+      .AddParameter("yesorno", _("Enable?"))
+      .MarkAsSimple();
+
+  aut.AddScopedAction("SetEffectDoubleParameter",
+                _("Effect parameter (number)"),
+                _("Change the value of a parameter of an effect.") + "\n" +
+                    _("You can find the parameter names (and change the effect "
+                      "names) in the effects window."),
+                _("Set _PARAM3_ to _PARAM4_ for effect _PARAM2_ of _PARAM0_"),
+                _("Effects"),
+                "res/actions/effect24.png",
+                "res/actions/effect.png")
+      .AddParameter("object", _("Object"))
+      .AddParameter("behavior", _("Behavior"), "EffectBehavior")
+      .AddParameter("objectEffectName", _("Effect name"))
+      .AddParameter("objectEffectParameterName", _("Parameter name"))
+      .AddParameter("expression", _("New value"))
+      .MarkAsSimple();
+
+  aut.AddScopedAction("SetEffectStringParameter",
+                _("Effect parameter (string)"),
+                _("Change the value (string) of a parameter of an effect.") +
+                    "\n" +
+                    _("You can find the parameter names (and change the effect "
+                      "names) in the effects window."),
+                _("Set _PARAM3_ to _PARAM4_ for effect _PARAM2_ of _PARAM0_"),
+                _("Effects"),
+                "res/actions/effect24.png",
+                "res/actions/effect.png")
+      .AddParameter("object", _("Object"))
+      .AddParameter("behavior", _("Behavior"), "EffectBehavior")
+      .AddParameter("objectEffectName", _("Effect name"))
+      .AddParameter("objectEffectParameterName", _("Parameter name"))
+      .AddParameter("string", _("New value"))
+      .MarkAsSimple();
+
+  aut.AddScopedAction("SetEffectBooleanParameter",
+                _("Effect parameter (enable or disable)"),
+                _("Enable or disable a parameter of an effect.") + "\n" +
+                    _("You can find the parameter names (and change the effect "
+                      "names) in the effects window."),
+                _("Enable _PARAM3_ for effect _PARAM2_ of _PARAM0_: _PARAM4_"),
+                _("Effects"),
+                "res/actions/effect24.png",
+                "res/actions/effect.png")
+      .AddParameter("object", _("Object"))
+      .AddParameter("behavior", _("Behavior"), "EffectBehavior")
+      .AddParameter("objectEffectName", _("Effect name"))
+      .AddParameter("objectEffectParameterName", _("Parameter name"))
+      .AddParameter("yesorno", _("Enable?"))
+      .MarkAsSimple();
+
+  aut.AddScopedCondition("IsEffectEnabled",
+                   _("Effect is enabled"),
+                   _("Check if the effect on an object is enabled."),
+                   _("Effect _PARAM2_ of _PARAM0_ is enabled"),
+                   _("Effects"),
+                   "res/actions/effect24.png",
+                   "res/actions/effect.png")
+      .AddParameter("object", _("Object"))
+      .AddParameter("behavior", _("Behavior"), "EffectBehavior")
+      .AddParameter("objectEffectName", _("Effect name"))
+      .MarkAsSimple();
+}
+
+}  // namespace gd
--- a/Core/GDCore/Extensions/Builtin/Capabilities/FlippableExtension.cpp
+++ b/Core/GDCore/Extensions/Builtin/Capabilities/FlippableExtension.cpp
@@ -0,0 +1,86 @@
+/*
+ * GDevelop Core
+ * Copyright 2008-2016 Florian Rival (Florian.Rival@gmail.com). All rights
+ * reserved. This project is released under the GNU Lesser General Public
+ * License.
+ */
+#include "GDCore/Extensions/Builtin/AllBuiltinExtensions.h"
+#include "GDCore/Extensions/Metadata/MultipleInstructionMetadata.h"
+#include "GDCore/Project/Behavior.h"
+#include "GDCore/Project/BehaviorsSharedData.h"
+#include "GDCore/Project/Object.h"
+#include "GDCore/Tools/Localization.h"
+
+using namespace std;
+namespace gd {
+
+void GD_CORE_API BuiltinExtensionsImplementer::ImplementsFlippableExtension(
+    gd::PlatformExtension& extension) {
+  extension
+      .SetExtensionInformation("FlippableCapability",
+                               _("Flippable capability"),
+                               _("Flip objects."),
+                               "Florian Rival",
+                               "Open source (MIT License)")
+      .SetExtensionHelpPath("/objects");
+  extension.AddInstructionOrExpressionGroupMetadata(_("Effects"))
+      .SetIcon("res/actions/effect24.png");
+
+  gd::BehaviorMetadata& aut = extension.AddBehavior(
+      "FlippableBehavior",
+      _("Flippable capability"),
+      "Flippable",
+      _("Flip objects."),
+      "",
+      "res/actions/flipX24.png",
+      "FlippableBehavior",
+      std::make_shared<gd::Behavior>(),
+      std::make_shared<gd::BehaviorsSharedData>())
+    .SetHidden();
+
+  aut.AddScopedAction("FlipX",
+                _("Flip the object horizontally"),
+                _("Flip the object horizontally"),
+                _("Flip horizontally _PARAM0_: _PARAM2_"),
+                _("Effects"),
+                "res/actions/flipX24.png",
+                "res/actions/flipX.png")
+      .AddParameter("object", _("Object"))
+      .AddParameter("behavior", _("Behavior"), "FlippableBehavior")
+      .AddParameter("yesorno", _("Activate flipping"))
+      .MarkAsSimple();
+
+  aut.AddScopedAction("FlipY",
+                _("Flip the object vertically"),
+                _("Flip the object vertically"),
+                _("Flip vertically _PARAM0_: _PARAM2_"),
+                _("Effects"),
+                "res/actions/flipY24.png",
+                "res/actions/flipY.png")
+      .AddParameter("object", _("Object"))
+      .AddParameter("behavior", _("Behavior"), "FlippableBehavior")
+      .AddParameter("yesorno", _("Activate flipping"))
+      .MarkAsSimple();
+
+  aut.AddScopedCondition("FlippedX",
+                   _("Horizontally flipped"),
+                   _("Check if the object is horizontally flipped"),
+                   _("_PARAM0_ is horizontally flipped"),
+                   _("Effects"),
+                   "res/actions/flipX24.png",
+                   "res/actions/flipX.png")
+      .AddParameter("object", _("Object"))
+      .AddParameter("behavior", _("Behavior"), "FlippableBehavior");
+
+  aut.AddScopedCondition("FlippedY",
+                   _("Vertically flipped"),
+                   _("Check if the object is vertically flipped"),
+                   _("_PARAM0_ is vertically flipped"),
+                   _("Effects"),
+                   "res/actions/flipY24.png",
+                   "res/actions/flipY.png")
+      .AddParameter("object", _("Object"))
+      .AddParameter("behavior", _("Behavior"), "FlippableBehavior");
+}
+
+}  // namespace gd
--- a/Core/GDCore/Extensions/Builtin/Capabilities/OpacityExtension.cpp
+++ b/Core/GDCore/Extensions/Builtin/Capabilities/OpacityExtension.cpp
@@ -0,0 +1,59 @@
+/*
+ * GDevelop Core
+ * Copyright 2008-2016 Florian Rival (Florian.Rival@gmail.com). All rights
+ * reserved. This project is released under the GNU Lesser General Public
+ * License.
+ */
+#include "GDCore/Extensions/Builtin/AllBuiltinExtensions.h"
+#include "GDCore/Extensions/Metadata/MultipleInstructionMetadata.h"
+#include "GDCore/Project/Behavior.h"
+#include "GDCore/Project/BehaviorsSharedData.h"
+#include "GDCore/Project/Object.h"
+#include "GDCore/Tools/Localization.h"
+
+using namespace std;
+namespace gd {
+
+void GD_CORE_API BuiltinExtensionsImplementer::ImplementsOpacityExtension(
+    gd::PlatformExtension& extension) {
+  extension
+      .SetExtensionInformation("OpacityCapability",
+                               _("Opacity capability"),
+                               _("Change the object opacity."),
+                               "Florian Rival",
+                               "Open source (MIT License)")
+      .SetExtensionHelpPath("/objects");
+  extension.AddInstructionOrExpressionGroupMetadata(_("Visibility"))
+      .SetIcon("res/actions/opacity24.png");
+
+  gd::BehaviorMetadata& aut = extension.AddBehavior(
+      "OpacityBehavior",
+      _("Opacity capability"),
+      "Opacity",
+      _("Change the object opacity."),
+      "",
+      "res/actions/opacity24.png",
+      "OpacityBehavior",
+      std::make_shared<gd::Behavior>(),
+      std::make_shared<gd::BehaviorsSharedData>())
+    .SetHidden();
+
+  aut.AddExpressionAndConditionAndAction(
+         "number",
+         "Value",
+         _("Opacity"),
+         _("the opacity of an object, between 0 (fully transparent) to 255 "
+           "(opaque)"),
+         _("the opacity"),
+         _("Visibility"),
+         "res/actions/opacity24.png")
+      .AddParameter("object", _("Object"))
+      .AddParameter("behavior", _("Behavior"), "OpacityBehavior")
+      .UseStandardParameters(
+          "number", gd::ParameterOptions::MakeNewOptions().SetDescription(
+                        _("Opacity (0-255)")))
+      .SetFunctionName("setOpacity")
+      .SetGetter("getOpacity");
+}
+
+}  // namespace gd
--- a/Core/GDCore/Extensions/Builtin/Capabilities/ResizableExtension.cpp
+++ b/Core/GDCore/Extensions/Builtin/Capabilities/ResizableExtension.cpp
@@ -0,0 +1,112 @@
+/*
+ * GDevelop Core
+ * Copyright 2008-2016 Florian Rival (Florian.Rival@gmail.com). All rights
+ * reserved. This project is released under the GNU Lesser General Public
+ * License.
+ */
+#include "GDCore/Extensions/Builtin/AllBuiltinExtensions.h"
+#include "GDCore/Project/Behavior.h"
+#include "GDCore/Project/BehaviorsSharedData.h"
+#include "GDCore/Project/Object.h"
+#include "GDCore/Tools/Localization.h"
+
+using namespace std;
+namespace gd {
+
+void GD_CORE_API BuiltinExtensionsImplementer::ImplementsResizableExtension(
+    gd::PlatformExtension &extension) {
+  extension
+      .SetExtensionInformation("ResizableCapability",
+                               _("Resizable capability"),
+                               _("Change the object dimensions."),
+                               "Florian Rival",
+                               "Open source (MIT License)")
+      .SetExtensionHelpPath("/objects");
+  extension.AddInstructionOrExpressionGroupMetadata(_("Size")).SetIcon(
+      "res/actions/scale24_black.png");
+
+  gd::BehaviorMetadata &aut =
+      extension
+          .AddBehavior("ResizableBehavior",
+                       _("Resizable capability"),
+                       "Resizable",
+                       _("Change the object dimensions."),
+                       "",
+                       "res/actions/scale24_black.png",
+                       "ResizableBehavior",
+                       std::make_shared<gd::Behavior>(),
+                       std::make_shared<gd::BehaviorsSharedData>())
+          .SetHidden();
+
+  aut.AddScopedAction("SetWidth",
+                      _("Width"),
+                      _("Change the width of the object."),
+                      _("the width"),
+                      _("Size"),
+                      "res/actions/scaleWidth24_black.png",
+                      "res/actions/scaleWidth_black.png")
+      .AddParameter("object", _("Object"))
+      .AddParameter("behavior", _("Behavior"), "ResizableBehavior")
+      .UseStandardOperatorParameters(
+          "number",
+          ParameterOptions::MakeNewOptions().SetDescription(_("Width")))
+      .MarkAsAdvanced();
+
+  aut.AddScopedCondition("Width",
+                         _("Width"),
+                         _("Compare the width of the object."),
+                         _("the width"),
+                         _("Size"),
+                         "res/conditions/scaleWidth24_black.png",
+                         "res/conditions/scaleWidth_black.png")
+      .AddParameter("object", _("Object"))
+      .AddParameter("behavior", _("Behavior"), "ResizableBehavior")
+      .UseStandardRelationalOperatorParameters(
+          "number",
+          ParameterOptions::MakeNewOptions().SetDescription(_("Width")))
+      .MarkAsAdvanced();
+
+  aut.AddScopedAction("SetHeight",
+                      _("Height"),
+                      _("Change the height of the object."),
+                      _("the height"),
+                      _("Size"),
+                      "res/actions/scaleHeight24_black.png",
+                      "res/actions/scaleHeight_black.png")
+      .AddParameter("object", _("Object"))
+      .AddParameter("behavior", _("Behavior"), "ResizableBehavior")
+      .UseStandardOperatorParameters(
+          "number",
+          ParameterOptions::MakeNewOptions().SetDescription(_("Height")))
+      .MarkAsAdvanced();
+
+  aut.AddScopedCondition("Height",
+                         _("Height"),
+                         _("Compare the height of the object."),
+                         _("the height"),
+                         _("Size"),
+                         "res/conditions/scaleHeight24_black.png",
+                         "res/conditions/scaleHeight_black.png")
+      .AddParameter("object", _("Object"))
+      .AddParameter("behavior", _("Behavior"), "ResizableBehavior")
+      .UseStandardRelationalOperatorParameters(
+          "number",
+          ParameterOptions::MakeNewOptions().SetDescription(_("Height")))
+      .MarkAsAdvanced();
+
+  aut.AddScopedAction(
+         "SetSize",
+         _("Size"),
+         _("Change the size of an object."),
+         _("Change the size of _PARAM0_: set to _PARAM2_ x _PARAM3_"),
+         _("Size"),
+         "res/actions/scale24_black.png",
+         "res/actions/scale_black.png")
+      .AddParameter("object", _("Object"))
+      .AddParameter("behavior", _("Behavior"), "ResizableBehavior")
+      .AddParameter("expression", _("Width"))
+      .AddParameter("expression", _("Height"))
+      .MarkAsAdvanced();
+}
+
+}  // namespace gd
--- a/Core/GDCore/Extensions/Builtin/Capabilities/ScalableExtension.cpp
+++ b/Core/GDCore/Extensions/Builtin/Capabilities/ScalableExtension.cpp
@@ -0,0 +1,90 @@
+/*
+ * GDevelop Core
+ * Copyright 2008-2016 Florian Rival (Florian.Rival@gmail.com). All rights
+ * reserved. This project is released under the GNU Lesser General Public
+ * License.
+ */
+#include "GDCore/Extensions/Builtin/AllBuiltinExtensions.h"
+#include "GDCore/Extensions/Metadata/MultipleInstructionMetadata.h"
+#include "GDCore/Project/Behavior.h"
+#include "GDCore/Project/BehaviorsSharedData.h"
+#include "GDCore/Project/Object.h"
+#include "GDCore/Tools/Localization.h"
+
+using namespace std;
+namespace gd {
+
+void GD_CORE_API BuiltinExtensionsImplementer::ImplementsScalableExtension(
+    gd::PlatformExtension& extension) {
+  extension
+      .SetExtensionInformation("ScalableCapability",
+                               _("Scalable capability"),
+                               _("Change the object scale."),
+                               "Florian Rival",
+                               "Open source (MIT License)")
+      .SetExtensionHelpPath("/objects");
+  extension.AddInstructionOrExpressionGroupMetadata(_("Size"))
+      .SetIcon("res/actions/scale24_black.png");
+
+  gd::BehaviorMetadata& aut = extension.AddBehavior(
+      "ScalableBehavior",
+      _("Scalable capability"),
+      "Scale",
+      _("Change the object scale."),
+      "",
+      "res/actions/scale24_black.png",
+      "ResizableBehavior",
+      std::make_shared<gd::Behavior>(),
+      std::make_shared<gd::BehaviorsSharedData>())
+    .SetHidden();
+
+  aut.AddExpressionAndConditionAndAction(
+         "number",
+         "Value",
+         _("Scale"),
+         _("the scale of the object (default scale is 1)"),
+         _("the scale"),
+         _("Scale"),
+         "res/actions/scale24_black.png")
+      .AddParameter("object", _("Object"))
+      .AddParameter("behavior", _("Behavior"), "ScalableBehavior")
+      .UseStandardParameters(
+          "number",
+          gd::ParameterOptions::MakeNewOptions().SetDescription(
+              _("Scale (1 by default)")))
+      .MarkAsAdvanced();
+
+  aut.AddExpressionAndConditionAndAction(
+         "number",
+         "X",
+         _("Scale on X axis"),
+         _("the scale on X axis of the object (default scale is 1)"),
+         _("the scale on X axis"),
+         _("Scale"),
+         "res/actions/scale24_black.png")
+      .AddParameter("object", _("Object"))
+      .AddParameter("behavior", _("Behavior"), "ScalableBehavior")
+      .UseStandardParameters(
+          "number",
+          gd::ParameterOptions::MakeNewOptions().SetDescription(
+              _("Scale (1 by default)")))
+      .MarkAsAdvanced();
+
+  aut.AddExpressionAndConditionAndAction(
+         "number",
+         "Y",
+         _("Scale on Y axis"),
+         _("the scale on Y axis of the object (default scale is 1)"),
+         _("the scale on Y axis"),
+         _("Scale"),
+         "res/actions/scale24_black.png")
+      .AddParameter("object", _("Object"))
+      .AddParameter("behavior", _("Behavior"), "ScalableBehavior")
+      .UseStandardParameters(
+          "number",
+          gd::ParameterOptions::MakeNewOptions().SetDescription(
+              _("Scale (1 by default)")))
+      .MarkAsAdvanced();
+}
+
+}  // namespace gd
--- a/Core/GDCore/Extensions/Builtin/SpriteExtension/Direction.cpp
+++ b/Core/GDCore/Extensions/Builtin/SpriteExtension/Direction.cpp
@@ -110,11 +110,11 @@ void Direction::UnserializeFrom(const gd::SerializerElement& element) {
            .GetBoolAttribute("automatic", true));

    if (spriteElement.HasChild("CustomCollisionMask"))
-      sprite.SetCollisionMaskAutomatic(
+      sprite.SetFullImageCollisionMask(
          !spriteElement.GetChild("CustomCollisionMask")
               .GetBoolAttribute("custom", false));
    else
-      sprite.SetCollisionMaskAutomatic(
+      sprite.SetFullImageCollisionMask(
          !spriteElement.GetBoolAttribute("hasCustomCollisionMask", false));

    std::vector<Polygon2d> mask;
@@ -173,7 +173,7 @@ void SaveSpritesDirection(const vector<Sprite>& sprites,
        .SetAttribute("automatic", sprites[i].IsDefaultCenterPoint());

    spriteElement.SetAttribute("hasCustomCollisionMask",
-                               !sprites[i].IsCollisionMaskAutomatic());
+                               !sprites[i].IsFullImageCollisionMask());

    gd::SerializerElement& collisionMaskElement =
        spriteElement.AddChild("customCollisionMask");
--- a/Core/GDCore/Extensions/Builtin/SpriteExtension/Sprite.cpp
+++ b/Core/GDCore/Extensions/Builtin/SpriteExtension/Sprite.cpp
@@ -4,7 +4,9 @@
 * reserved. This project is released under the MIT License.
 */
 #include "GDCore/Extensions/Builtin/SpriteExtension/Sprite.h"
+
 #include <iostream>
+
 #include "GDCore/Extensions/Builtin/SpriteExtension/Polygon2d.h"

 using namespace std;
@@ -14,11 +16,10 @@ namespace gd {
 Point Sprite::badPoint("");

 Sprite::Sprite()
-    : automaticCollisionMask(true),
+    : fullImageCollisionMask(false),
      origine("origine"),
      centre("centre"),
-      automaticCentre(true) {
-}
+      automaticCentre(true) {}

 Sprite::~Sprite(){};

--- a/Core/GDCore/Extensions/Builtin/SpriteExtension/Sprite.h
+++ b/Core/GDCore/Extensions/Builtin/SpriteExtension/Sprite.h
@@ -7,6 +7,7 @@
 #ifndef SPRITE_H
 #define SPRITE_H
 #include <memory>
+
 #include "GDCore/Extensions/Builtin/SpriteExtension/Point.h"
 #include "GDCore/Extensions/Builtin/SpriteExtension/Polygon2d.h"
 #include "GDCore/String.h"
@@ -43,7 +44,7 @@ class GD_CORE_API Sprite {

  /**
   * \brief Get the collision mask (custom or automatically generated owing to
-   * IsCollisionMaskAutomatic())
+   * IsFullImageCollisionMask())
   *
   * \warning If the image has not been loaded ( using LoadImage ) and the
   * collision mask is set as automatic, the returned mask won't be correct.
@@ -66,7 +67,7 @@ class GD_CORE_API Sprite {

  /**
   * \brief Set the custom collision mask.
-   * Call then `SetCollisionMaskAutomatic(false)` to use it.
+   * Call then `SetFullImageCollisionMask(false)` to use it.
   */
  void SetCustomCollisionMask(const std::vector<Polygon2d>& collisionMask);

@@ -74,15 +75,15 @@ class GD_CORE_API Sprite {
   * \brief Return true if the collision mask is a bounding box, false if a
   * custom collision mask is used.
   */
-  inline bool IsCollisionMaskAutomatic() const {
-    return automaticCollisionMask;
+  inline bool IsFullImageCollisionMask() const {
+    return fullImageCollisionMask;
  }

  /**
   * \brief Un/set use of the custom collision mask.
   */
-  inline void SetCollisionMaskAutomatic(bool enabled) {
-    automaticCollisionMask = enabled;
+  inline void SetFullImageCollisionMask(bool enabled) {
+    fullImageCollisionMask = enabled;
  };

  /**
@@ -161,9 +162,9 @@ class GD_CORE_API Sprite {
 private:
  gd::String image;  ///< Name of the image to be loaded in Image Manager.

-  bool automaticCollisionMask;  ///< True to use the custom collision mask.
-                                ///< Otherwise, a basic bounding box is returned
-                                ///< by GetCollisionMask()
+  bool fullImageCollisionMask;  ///< True to use a bounding box wrapping the
+                                ///< whole image as collision mask. If false,
+                                ///< custom collision mask is used.
  std::vector<Polygon2d> customCollisionMask;  ///< Custom collision mask

  std::vector<Point> points;  ///< List of the points used by the sprite
--- a/Core/GDCore/Extensions/Builtin/SpriteExtension/SpriteExtension.cpp
+++ b/Core/GDCore/Extensions/Builtin/SpriteExtension/SpriteExtension.cpp
@@ -2,7 +2,7 @@
 * GDevelop Core
 * Copyright 2008-2016 Florian Rival (Florian.Rival@gmail.com). All rights
 * reserved. This project is released under the GNU Lesser General Public
- * LicenFse.
+ * License.
 */
 #include "GDCore/Extensions/Builtin/AllBuiltinExtensions.h"
 #include "GDCore/Extensions/Builtin/SpriteExtension/SpriteObject.h"
@@ -32,8 +32,15 @@ void GD_CORE_API BuiltinExtensionsImplementer::ImplementsSpriteExtension(
                                   _("Animated object which can be used for "
                                     "most elements of a game"),
                                   "CppPlatform/Extensions/spriteicon.png")
-          .SetCategoryFullName(_("General"));
+          .SetCategoryFullName(_("General"))
+          .AddDefaultBehavior("EffectCapability::EffectBehavior")
+          .AddDefaultBehavior("ResizableCapability::ResizableBehavior")
+          .AddDefaultBehavior("ScalableCapability::ScalableBehavior")
+          .AddDefaultBehavior("FlippableCapability::FlippableBehavior")
+          .AddDefaultBehavior("OpacityCapability::OpacityBehavior")
+          .AddDefaultBehavior("AnimatableCapability::AnimatableBehavior");

+  // Deprecated
  obj.AddAction("Opacity",
                _("Sprite opacity"),
                _("Change the opacity of a Sprite. 0 is fully transparent, 255 "
@@ -48,8 +55,10 @@ void GD_CORE_API BuiltinExtensionsImplementer::ImplementsSpriteExtension(
          "number",
          ParameterOptions::MakeNewOptions().SetDescription(
              _("Opacity (0-255)")))
-      .MarkAsSimple();
+      .MarkAsSimple()
+      .SetHidden();

+  // Deprecated
  obj.AddAction("ChangeAnimation",
                _("Change the animation"),
                _("Change the animation of the object, using the animation "
@@ -62,8 +71,10 @@ void GD_CORE_API BuiltinExtensionsImplementer::ImplementsSpriteExtension(
      .AddParameter("object", _("Object"), "Sprite")
      .UseStandardOperatorParameters("number",
                                     ParameterOptions::MakeNewOptions())
+      .SetHidden()
      .MarkAsSimple();

+  // Deprecated
  obj.AddAction("SetAnimationName",
                _("Change the animation (by name)"),
                _("Change the animation of the object, using the name of the "
@@ -75,6 +86,7 @@ void GD_CORE_API BuiltinExtensionsImplementer::ImplementsSpriteExtension(

      .AddParameter("object", _("Object"), "Sprite")
      .AddParameter("objectAnimationName", _("Animation name"))
+      .SetHidden()
      .MarkAsAdvanced();

  obj.AddAction(
@@ -107,6 +119,7 @@ void GD_CORE_API BuiltinExtensionsImplementer::ImplementsSpriteExtension(
                                     ParameterOptions::MakeNewOptions())
      .MarkAsAdvanced();

+  // Deprecated
  obj.AddAction("PauseAnimation",
                _("Pause the animation"),
                _("Pause the animation of the object"),
@@ -116,8 +129,10 @@ void GD_CORE_API BuiltinExtensionsImplementer::ImplementsSpriteExtension(
                "res/actions/animation.png")

      .AddParameter("object", _("Object"), "Sprite")
+      .SetHidden()
      .MarkAsSimple();

+  // Deprecated
  obj.AddAction("PlayAnimation",
                _("Play the animation"),
                _("Play the animation of the object"),
@@ -127,8 +142,10 @@ void GD_CORE_API BuiltinExtensionsImplementer::ImplementsSpriteExtension(
                "res/actions/animation.png")

      .AddParameter("object", _("Object"), "Sprite")
+      .SetHidden()
      .MarkAsSimple();

+  // Deprecated
  obj.AddAction(
         "ChangeAnimationSpeedScale",
         _("Animation speed scale"),
@@ -143,8 +160,10 @@ void GD_CORE_API BuiltinExtensionsImplementer::ImplementsSpriteExtension(
      .UseStandardOperatorParameters(
          "number",
          ParameterOptions::MakeNewOptions().SetDescription(_("Speed scale")))
+      .SetHidden()
      .MarkAsSimple();

+  // Deprecated
  obj.AddAction("TourneVersPos",
                "Rotate an object toward a position",
                "Rotate an object towards a position.",
@@ -159,8 +178,9 @@ void GD_CORE_API BuiltinExtensionsImplementer::ImplementsSpriteExtension(
      .AddParameter("expression", _("Angular speed (degrees per second)"))
      .SetDefaultValue("0")
      .AddCodeOnlyParameter("currentScene", "")
-      .SetHidden();  // Deprecated
+      .SetHidden();

+  // Deprecated
  obj.AddAction("ChangeScale",
                _("Scale"),
                _("Modify the scale of the specified object."),
@@ -174,8 +194,10 @@ void GD_CORE_API BuiltinExtensionsImplementer::ImplementsSpriteExtension(
          "number",
          ParameterOptions::MakeNewOptions().SetDescription(
              _("Scale (1 by default)")))
-      .MarkAsAdvanced();
+      .MarkAsAdvanced()
+      .SetHidden();

+  // Deprecated
  obj.AddAction("ChangeScaleWidth",
                _("Scale on X axis"),
                _("Modify the scale of the width of an object."),
@@ -189,8 +211,10 @@ void GD_CORE_API BuiltinExtensionsImplementer::ImplementsSpriteExtension(
          "number",
          ParameterOptions::MakeNewOptions().SetDescription(
              _("Scale (1 by default)")))
-      .MarkAsAdvanced();
+      .MarkAsAdvanced()
+      .SetHidden();

+  // Deprecated
  obj.AddAction("ChangeScaleHeight",
                _("Scale on Y axis"),
                _("Modify the scale of the height of an object."),
@@ -204,8 +228,10 @@ void GD_CORE_API BuiltinExtensionsImplementer::ImplementsSpriteExtension(
          "number",
          ParameterOptions::MakeNewOptions().SetDescription(
              _("Scale (1 by default)")))
-      .MarkAsAdvanced();
+      .MarkAsAdvanced()
+      .SetHidden();

+  // Deprecated
  obj.AddAction("ChangeWidth",
                _("Width"),
                _("Change the width of a Sprite object."),
@@ -217,8 +243,10 @@ void GD_CORE_API BuiltinExtensionsImplementer::ImplementsSpriteExtension(
      .AddParameter("object", _("Object"), "Sprite")
      .UseStandardOperatorParameters("number",
                                     ParameterOptions::MakeNewOptions())
-      .MarkAsAdvanced();
+      .MarkAsAdvanced()
+      .SetHidden();

+  // Deprecated
  obj.AddCondition("Width",
                   _("Width"),
                   _("Compare the width of a Sprite object."),
@@ -230,8 +258,10 @@ void GD_CORE_API BuiltinExtensionsImplementer::ImplementsSpriteExtension(
      .AddParameter("object", _("Object"), "Sprite")
      .UseStandardRelationalOperatorParameters(
          "number", ParameterOptions::MakeNewOptions())
-      .MarkAsAdvanced();
+      .MarkAsAdvanced()
+      .SetHidden();

+  // Deprecated
  obj.AddAction("ChangeHeight",
                _("Height"),
                _("Change the height of a Sprite object."),
@@ -243,8 +273,10 @@ void GD_CORE_API BuiltinExtensionsImplementer::ImplementsSpriteExtension(
      .AddParameter("object", _("Object"), "Sprite")
      .UseStandardOperatorParameters("number",
                                     ParameterOptions::MakeNewOptions())
-      .MarkAsAdvanced();
+      .MarkAsAdvanced()
+      .SetHidden();

+  // Deprecated
  obj.AddCondition("Height",
                   _("Height"),
                   _("Compare the height of a Sprite object."),
@@ -256,8 +288,10 @@ void GD_CORE_API BuiltinExtensionsImplementer::ImplementsSpriteExtension(
      .AddParameter("object", _("Object"), "Sprite")
      .UseStandardRelationalOperatorParameters(
          "number", ParameterOptions::MakeNewOptions())
-      .MarkAsAdvanced();
+      .MarkAsAdvanced()
+      .SetHidden();

+  // Deprecated
  obj.AddAction("SetSize",
                _("Size"),
                _("Change the size of an object."),
@@ -269,8 +303,10 @@ void GD_CORE_API BuiltinExtensionsImplementer::ImplementsSpriteExtension(
      .AddParameter("object", _("Object"))
      .AddParameter("expression", _("Width"))
      .AddParameter("expression", _("Height"))
-      .MarkAsAdvanced();
+      .MarkAsAdvanced()
+      .SetHidden();

+  // Deprecated
  obj.AddCondition(
         "Animation",
         _("Current animation"),
@@ -283,11 +319,13 @@ void GD_CORE_API BuiltinExtensionsImplementer::ImplementsSpriteExtension(
      .AddParameter("object", _("Object"), "Sprite")
      .UseStandardRelationalOperatorParameters(
          "number", ParameterOptions::MakeNewOptions())
+      .SetHidden()
      .MarkAsAdvanced();

+  // Deprecated
  obj.AddCondition("AnimationName",
                   _("Current animation name"),
-                   _("Check the animation by played by the object."),
+                   _("Check the animation played by the object."),
                   _("The animation of _PARAM0_ is _PARAM1_"),
                   _("Animations and images"),
                   "res/conditions/animation24.png",
@@ -295,6 +333,7 @@ void GD_CORE_API BuiltinExtensionsImplementer::ImplementsSpriteExtension(

      .AddParameter("object", _("Object"), "Sprite")
      .AddParameter("objectAnimationName", _("Animation name"))
+      .SetHidden()
      .MarkAsAdvanced();

  obj.AddCondition(
@@ -328,6 +367,7 @@ void GD_CORE_API BuiltinExtensionsImplementer::ImplementsSpriteExtension(
          "number", ParameterOptions::MakeNewOptions())
      .MarkAsAdvanced();

+  // Deprecated
  obj.AddCondition("AnimStopped",
                   _("Animation paused"),
                   _("Check if the animation of an object is paused."),
@@ -337,8 +377,10 @@ void GD_CORE_API BuiltinExtensionsImplementer::ImplementsSpriteExtension(
                   "res/conditions/animation.png")

      .AddParameter("object", _("Object"), "Sprite")
+      .SetHidden()
      .MarkAsSimple();

+  // Deprecated
  obj.AddCondition("AnimationEnded",
                   _("Animation finished"),
                   _("Check if the animation being played by the Sprite object "
@@ -352,6 +394,7 @@ void GD_CORE_API BuiltinExtensionsImplementer::ImplementsSpriteExtension(
      .MarkAsSimple()
      .SetHidden();

+  // Deprecated
  obj.AddCondition("AnimationEnded2",
                   _("Animation finished"),
                   _("Check if the animation being played by the Sprite object "
@@ -362,6 +405,7 @@ void GD_CORE_API BuiltinExtensionsImplementer::ImplementsSpriteExtension(
                   "res/conditions/animation.png")

      .AddParameter("object", _("Object"), "Sprite")
+      .SetHidden()
      .MarkAsSimple();

  obj.AddCondition("ScaleWidth",
@@ -394,6 +438,7 @@ void GD_CORE_API BuiltinExtensionsImplementer::ImplementsSpriteExtension(
              _("Scale (1 by default)")))
      .MarkAsAdvanced();

+  // Deprecated
  obj.AddCondition("Opacity",
                   _("Opacity"),
                   _("Compare the opacity of a Sprite, between 0 (fully "
@@ -408,7 +453,8 @@ void GD_CORE_API BuiltinExtensionsImplementer::ImplementsSpriteExtension(
          "number",
          ParameterOptions::MakeNewOptions().SetDescription(
              _("Opacity to compare to (0-255)")))
-      .MarkAsSimple();
+      .MarkAsSimple()
+      .SetHidden();

  obj.AddCondition(
         "BlendMode",
@@ -456,9 +502,9 @@ void GD_CORE_API BuiltinExtensionsImplementer::ImplementsSpriteExtension(
                _("Effects"),
                "res/actions/flipX24.png",
                "res/actions/flipX.png")
-
      .AddParameter("object", _("Object"), "Sprite")
      .AddParameter("yesorno", _("Activate flipping"))
+      .SetHidden()
      .MarkAsSimple();

  obj.AddAction("FlipY",
@@ -468,9 +514,9 @@ void GD_CORE_API BuiltinExtensionsImplementer::ImplementsSpriteExtension(
                _("Effects"),
                "res/actions/flipY24.png",
                "res/actions/flipY.png")
-
      .AddParameter("object", _("Object"), "Sprite")
      .AddParameter("yesorno", _("Activate flipping"))
+      .SetHidden()
      .MarkAsSimple();

  obj.AddCondition("FlippedX",
@@ -480,8 +526,8 @@ void GD_CORE_API BuiltinExtensionsImplementer::ImplementsSpriteExtension(
                   _("Effects"),
                   "res/actions/flipX24.png",
                   "res/actions/flipX.png")
-
-      .AddParameter("object", _("Object"), "Sprite");
+      .AddParameter("object", _("Object"), "Sprite")
+      .SetHidden();

  obj.AddCondition("FlippedY",
                   _("Vertically flipped"),
@@ -490,9 +536,10 @@ void GD_CORE_API BuiltinExtensionsImplementer::ImplementsSpriteExtension(
                   _("Effects"),
                   "res/actions/flipY24.png",
                   "res/actions/flipY.png")
+      .AddParameter("object", _("Object"), "Sprite")
+      .SetHidden();

-      .AddParameter("object", _("Object"), "Sprite");
-
+  // Deprecated
  obj.AddAction("TourneVers",
                "Rotate an object toward another",
                "Rotate an object towards another.",
@@ -504,7 +551,7 @@ void GD_CORE_API BuiltinExtensionsImplementer::ImplementsSpriteExtension(
      .AddParameter("object", _("Object"), "Sprite")
      .AddParameter("objectPtr", "Rotate toward this object")
      .AddCodeOnlyParameter("currentScene", "")
-      .SetHidden();  // Deprecated
+      .SetHidden();

  obj.AddExpression("X",
                    _("X position of a point"),
@@ -542,6 +589,7 @@ void GD_CORE_API BuiltinExtensionsImplementer::ImplementsSpriteExtension(
      .AddParameter("object", _("Object"), "Sprite")
      .AddParameter("objectPointName", _("Name of the point"));

+  // Deprecated
  obj.AddExpression("Direc",
                    _("Direction"),
                    _("Direction of the object"),
@@ -550,6 +598,7 @@ void GD_CORE_API BuiltinExtensionsImplementer::ImplementsSpriteExtension(
      .SetHidden()
      .AddParameter("object", _("Object"), "Sprite");

+  // Deprecated
  obj.AddExpression("Direction",
                    _("Direction"),
                    _("Direction of the object"),
@@ -559,6 +608,7 @@ void GD_CORE_API BuiltinExtensionsImplementer::ImplementsSpriteExtension(
                    // interface.
      .AddParameter("object", _("Object"), "Sprite");

+  // Deprecated
  obj.AddExpression("Anim",
                    _("Animation"),
                    _("Animation of the object"),
@@ -567,18 +617,22 @@ void GD_CORE_API BuiltinExtensionsImplementer::ImplementsSpriteExtension(
      .SetHidden()
      .AddParameter("object", _("Object"), "Sprite");

+  // Deprecated
  obj.AddExpression("Animation",
                    _("Animation"),
                    _("Animation of the object"),
                    _("Animations and images"),
                    "res/actions/animation.png")
+      .SetHidden()
      .AddParameter("object", _("Object"), "Sprite");

+  // Deprecated
  obj.AddStrExpression("AnimationName",
                       _("Animation name"),
                       _("Name of the animation of the object"),
                       _("Animations and images"),
                       "res/actions/animation.png")
+      .SetHidden()
      .AddParameter("object", _("Object"), "Sprite");

  obj.AddExpression("Sprite",
@@ -595,11 +649,13 @@ void GD_CORE_API BuiltinExtensionsImplementer::ImplementsSpriteExtension(
                    "res/actions/sprite.png")
      .AddParameter("object", _("Object"), "Sprite");

+  // Deprecated
  obj.AddExpression("AnimationSpeedScale",
                    _("Animation speed scale"),
                    _("Animation speed scale"),
                    _("Animations and images"),
                    "res/actions/animation.png")
+      .SetHidden()
      .AddParameter("object", _("Object"), "Sprite");

  obj.AddExpression("ScaleX",
@@ -607,6 +663,7 @@ void GD_CORE_API BuiltinExtensionsImplementer::ImplementsSpriteExtension(
                    _("Scale of the width of an object"),
                    _("Size"),
                    "res/actions/scaleWidth_black.png")
+      .SetHidden()
      .AddParameter("object", _("Object"), "Sprite");

  obj.AddExpression("ScaleY",
@@ -614,14 +671,17 @@ void GD_CORE_API BuiltinExtensionsImplementer::ImplementsSpriteExtension(
                    _("Scale of the height of an object"),
                    _("Size"),
                    "res/actions/scaleHeight_black.png")
+      .SetHidden()
      .AddParameter("object", _("Object"), "Sprite");

+  // Deprecated
  obj.AddExpression("Opacity",
                    _("Opacity"),
                    _("Opacity"),
                    _("Opacity"),
                    "res/actions/opacity.png")
-      .AddParameter("object", _("Object"), "Sprite");
+      .AddParameter("object", _("Object"), "Sprite")
+      .SetHidden();

  extension
      .AddCondition("Collision",
--- a/Core/GDCore/Extensions/Builtin/SpriteExtension/SpriteObject.cpp
+++ b/Core/GDCore/Extensions/Builtin/SpriteExtension/SpriteObject.cpp
@@ -25,13 +25,16 @@ namespace gd {

 Animation SpriteObject::badAnimation;

-SpriteObject::SpriteObject() : updateIfNotVisible(false) {}
+SpriteObject::SpriteObject()
+    : updateIfNotVisible(false), adaptCollisionMaskAutomatically(true) {}

 SpriteObject::~SpriteObject(){};

 void SpriteObject::DoUnserializeFrom(gd::Project& project,
                                     const gd::SerializerElement& element) {
  updateIfNotVisible = element.GetBoolAttribute("updateIfNotVisible", true);
+  adaptCollisionMaskAutomatically =
+      element.GetBoolAttribute("adaptCollisionMaskAutomatically", false);

  RemoveAllAnimations();
  const gd::SerializerElement& animationsElement =
@@ -80,6 +83,8 @@ void SpriteObject::DoUnserializeFrom(gd::Project& project,

 void SpriteObject::DoSerializeTo(gd::SerializerElement& element) const {
  element.SetAttribute("updateIfNotVisible", updateIfNotVisible);
+  element.SetAttribute("adaptCollisionMaskAutomatically",
+                       adaptCollisionMaskAutomatically);

  // Animations
  gd::SerializerElement& animationsElement = element.AddChild("animations");
--- a/Core/GDCore/Extensions/Builtin/SpriteExtension/SpriteObject.h
+++ b/Core/GDCore/Extensions/Builtin/SpriteExtension/SpriteObject.h
@@ -47,8 +47,7 @@ class GD_CORE_API SpriteObject : public gd::ObjectConfiguration {
  void ExposeResources(gd::ArbitraryResourceWorker& worker) override;

  std::map<gd::String, gd::PropertyDescriptor> GetProperties() const override;
-  bool UpdateProperty(const gd::String& name,
-                      const gd::String& value) override;
+  bool UpdateProperty(const gd::String& name, const gd::String& value) override;

  std::map<gd::String, gd::PropertyDescriptor> GetInitialInstanceProperties(
      const gd::InitialInstance& position,
@@ -118,14 +117,30 @@ class GD_CORE_API SpriteObject : public gd::ObjectConfiguration {
  const std::vector<Animation>& GetAllAnimations() const { return animations; }

  /**
-   * \brief Set if the object animation should be played even if the object is hidden
-   * or far from the camera.
+   * @brief Check if the collision mask adapts automatically to the animation.
   */
-  void SetUpdateIfNotVisible(bool updateIfNotVisible_) { updateIfNotVisible = updateIfNotVisible_; }
+  bool AdaptCollisionMaskAutomatically() const {
+    return adaptCollisionMaskAutomatically;
+  }

  /**
-   * \brief Check if the object animation should be played even if the object is hidden
-   * or far from the camera (false by default).
+   * @brief Set if the collision mask adapts automatically to the animation.
+   */
+  void SetAdaptCollisionMaskAutomatically(bool enable) {
+    adaptCollisionMaskAutomatically = enable;
+  }
+
+  /**
+   * \brief Set if the object animation should be played even if the object is
+   * hidden or far from the camera.
+   */
+  void SetUpdateIfNotVisible(bool updateIfNotVisible_) {
+    updateIfNotVisible = updateIfNotVisible_;
+  }
+
+  /**
+   * \brief Check if the object animation should be played even if the object
+   * is hidden or far from the camera (false by default).
   */
  bool GetUpdateIfNotVisible() const { return updateIfNotVisible; }
  ///@}
@@ -137,11 +152,15 @@ class GD_CORE_API SpriteObject : public gd::ObjectConfiguration {

  mutable std::vector<Animation> animations;
  bool updateIfNotVisible;  ///< If set to true, ask the game engine to play
-                            ///< object animation even if hidden or far from the
-                            ///< screen.
+                            ///< object animation even if hidden or far from
+                            ///< the screen.

-  static Animation badAnimation;  //< Bad animation when an out of bound
-                                  // animation is requested.
+  static Animation badAnimation;         //< Bad animation when an out of bound
+                                         // animation is requested.
+  bool adaptCollisionMaskAutomatically;  ///< If set to true, the collision
+                                         ///< mask will be automatically
+                                         ///< adapted to the animation of the
+                                         ///< object.
 };

 }  // namespace gd
--- a/Core/GDCore/Extensions/Builtin/StringInstructionsExtension.cpp
+++ b/Core/GDCore/Extensions/Builtin/StringInstructionsExtension.cpp
@@ -172,7 +172,7 @@ BuiltinExtensionsImplementer::ImplementsStringInstructionsExtension(
          _("Search the last occurrence in a text, starting from a position"),
          _("Search in a text the last occurrence, starting from a position "
            "(return "
-            " the position of the result, from the beginning of the string, or "
+            "the position of the result, from the beginning of the string, or "
            "-1 if not found)"),
          "",
          "res/conditions/toujours24_black.png")
--- a/Core/GDCore/Extensions/Metadata/AbstractFunctionMetadata.h
+++ b/Core/GDCore/Extensions/Metadata/AbstractFunctionMetadata.h
@@ -0,0 +1,135 @@
+/*
+ * GDevelop Core
+ * Copyright 2008-2016 Florian Rival (Florian.Rival@gmail.com). All rights
+ * reserved. This project is released under the MIT License.
+ */
+
+#pragma once
+
+#include <algorithm>
+#include <functional>
+#include <map>
+#include <memory>
+
+#include "GDCore/Events/Instruction.h"
+#include "GDCore/String.h"
+#include "ParameterMetadata.h"
+#include "ParameterOptions.h"
+
+namespace gd {
+class Project;
+class Layout;
+class EventsCodeGenerator;
+class EventsCodeGenerationContext;
+class SerializerElement;
+} // namespace gd
+
+namespace gd {
+
+/**
+ * \brief Describe user-friendly information about an expression or an
+ * instruction (action or condition), its parameters and the function name as
+ * well as other information for code generation.
+ *
+ * \ingroup Events
+ */
+class GD_CORE_API AbstractFunctionMetadata {
+public:
+  AbstractFunctionMetadata(){};
+  virtual ~AbstractFunctionMetadata(){};
+
+  /**
+   * \see gd::InstructionMetadata::AddParameter
+   */
+  virtual AbstractFunctionMetadata &
+  AddParameter(const gd::String &type, const gd::String &label,
+               const gd::String &supplementaryInformation = "",
+               bool parameterIsOptional = false) = 0;
+
+  /**
+   * \see gd::InstructionMetadata::AddCodeOnlyParameter
+   */
+  virtual AbstractFunctionMetadata &
+  AddCodeOnlyParameter(const gd::String &type,
+                       const gd::String &supplementaryInformation) = 0;
+
+  /**
+   * \see gd::InstructionMetadata::SetDefaultValue
+   */
+  virtual AbstractFunctionMetadata &
+  SetDefaultValue(const gd::String &defaultValue) = 0;
+
+  /**
+   * \see gd::InstructionMetadata::SetParameterExtraInfo
+   */
+  virtual AbstractFunctionMetadata &
+  SetParameterExtraInfo(const gd::String &defaultValue) = 0;
+
+  /**
+   * \see gd::InstructionMetadata::SetParameterLongDescription
+   */
+  virtual AbstractFunctionMetadata &
+  SetParameterLongDescription(const gd::String &longDescription) = 0;
+
+  /**
+   * \see gd::InstructionMetadata::SetHidden
+   */
+  virtual AbstractFunctionMetadata &SetHidden() = 0;
+
+  /**
+   * Set that the instruction is private - it can't be used outside of the
+   * object/ behavior that it is attached too.
+   */
+  virtual AbstractFunctionMetadata &SetPrivate() = 0;
+
+  /**
+   * Set that the instruction can be used in layouts or external events.
+   */
+  virtual AbstractFunctionMetadata &SetRelevantForLayoutEventsOnly() = 0;
+
+  /**
+   * Set that the instruction can be used in function events.
+   */
+  virtual AbstractFunctionMetadata &SetRelevantForFunctionEventsOnly() = 0;
+
+  /**
+   * Set that the instruction can be used in asynchronous function events.
+   */
+  virtual AbstractFunctionMetadata &
+  SetRelevantForAsynchronousFunctionEventsOnly() = 0;
+
+  /**
+   * Set that the instruction can be used in custom object events.
+   */
+  virtual AbstractFunctionMetadata &SetRelevantForCustomObjectEventsOnly() = 0;
+
+  /**
+   * \brief Set the function that should be called when generating the source
+   * code from events.
+   * \param functionName the name of the function to call
+   * \note Shortcut for `codeExtraInformation.SetFunctionName`.
+   */
+  virtual AbstractFunctionMetadata &
+  SetFunctionName(const gd::String &functionName) = 0;
+
+  /**
+   * \brief Erase any existing include file and add the specified include.
+   */
+  virtual AbstractFunctionMetadata &
+  SetIncludeFile(const gd::String &includeFile) = 0;
+
+  /**
+   * \brief Add a file to the already existing include files.
+   */
+  virtual AbstractFunctionMetadata &
+  AddIncludeFile(const gd::String &includeFile) = 0;
+
+  /**
+   * \brief Get the files that must be included to use the instruction.
+   */
+  virtual const std::vector<gd::String> &GetIncludeFiles() const = 0;
+
+private:
+};
+
+} // namespace gd
--- a/Core/GDCore/Extensions/Metadata/BehaviorMetadata.cpp
+++ b/Core/GDCore/Extensions/Metadata/BehaviorMetadata.cpp
@@ -34,8 +34,7 @@ BehaviorMetadata::BehaviorMetadata(
      className(className_),
      iconFilename(icon24x24),
      instance(instance_),
-      sharedDatasInstance(sharedDatasInstance_),
-      isEventBased(false) {
+      sharedDatasInstance(sharedDatasInstance_) {
  SetFullName(gd::String(fullname_));
  SetDescription(gd::String(description_));
  SetDefaultName(gd::String(defaultName_));
@@ -52,29 +51,6 @@ BehaviorMetadata::BehaviorMetadata(
  if (sharedDatasInstance) sharedDatasInstance->SetTypeName(nameWithNamespace);
 }

-BehaviorMetadata::BehaviorMetadata(
-    const gd::String& extensionNamespace,
-    const gd::String& nameWithNamespace,
-    const gd::String& fullname_,
-    const gd::String& defaultName_,
-    const gd::String& description_,
-    const gd::String& group_,
-    const gd::String& icon24x24_): BehaviorMetadata(
-        extensionNamespace,
-        nameWithNamespace,
-        fullname_,
-        defaultName_,
-        description_,
-        group_,
-        icon24x24_,
-        // Class name is the name, actually unused
-        defaultName_,
-        // It is only used to get the name for GetName.
-        gd::make_unique<gd::Behavior>("", nameWithNamespace),
-        nullptr){
-  isEventBased = true;
-};
-
 gd::InstructionMetadata& BehaviorMetadata::AddCondition(
    const gd::String& name,
    const gd::String& fullname,
@@ -420,10 +396,6 @@ const gd::String& BehaviorMetadata::GetName() const {
 }

 gd::Behavior& BehaviorMetadata::Get() const {
-  if (isEventBased) {
-    gd::LogFatalError("Error: Event-based behaviors don't have blueprint. "
-                      "This method should not never be called.");
-  }
  if (!instance) {
    gd::LogFatalError(
        "Trying to get a behavior from a BehaviorMetadata that has no "
@@ -434,11 +406,20 @@ gd::Behavior& BehaviorMetadata::Get() const {
 }

 gd::BehaviorsSharedData* BehaviorMetadata::GetSharedDataInstance() const { 
-  if (isEventBased) {
-    gd::LogFatalError("Error: Event-based behaviors don't have blueprint. "
-                      "This method should not never be called.");
-  }
  return sharedDatasInstance.get();
 }

+const std::vector<gd::String>& BehaviorMetadata::GetRequiredBehaviorTypes() const {
+  requiredBehaviors.clear();
+  for (auto& property : Get().GetProperties()) {
+    const String& propertyName = property.first;
+    const gd::PropertyDescriptor& propertyDescriptor = property.second;
+
+    if (propertyDescriptor.GetType() == "Behavior") {
+      requiredBehaviors.push_back(propertyDescriptor.GetExtraInfo()[0]);
+    }
+  }
+  return requiredBehaviors;
+}
+
 }  // namespace gd
--- a/Core/GDCore/Extensions/Metadata/BehaviorMetadata.h
+++ b/Core/GDCore/Extensions/Metadata/BehaviorMetadata.h
@@ -3,8 +3,10 @@
 * Copyright 2008-2016 Florian Rival (Florian.Rival@gmail.com). All rights
 * reserved. This project is released under the MIT License.
 */
-#ifndef BEHAVIORMETADATA_H
-#define BEHAVIORMETADATA_H
+#pragma once
+
+#include "InstructionOrExpressionContainerMetadata.h"
+
 #include <map>

 #include "GDCore/Extensions/Metadata/ExpressionMetadata.h"
@@ -25,7 +27,7 @@ namespace gd {
 *
 * \ingroup Events
 */
-class GD_CORE_API BehaviorMetadata {
+class GD_CORE_API BehaviorMetadata : public InstructionOrExpressionContainerMetadata {
 public:
  BehaviorMetadata(
      const gd::String& extensionNamespace,
@@ -67,7 +69,7 @@ class GD_CORE_API BehaviorMetadata {
                                        const gd::String& sentence_,
                                        const gd::String& group_,
                                        const gd::String& icon_,
-                                        const gd::String& smallicon_);
+                                        const gd::String& smallicon_) override;

  /**
   * Declare a new action as being part of the behavior.
@@ -80,7 +82,7 @@ class GD_CORE_API BehaviorMetadata {
                                     const gd::String& sentence_,
                                     const gd::String& group_,
                                     const gd::String& icon_,
-                                     const gd::String& smallicon_);
+                                     const gd::String& smallicon_) override;

  /**
   * Declare a new condition as being part of the behavior.
@@ -91,7 +93,7 @@ class GD_CORE_API BehaviorMetadata {
                                              const gd::String& sentence_,
                                              const gd::String& group_,
                                              const gd::String& icon_,
-                                              const gd::String& smallicon_);
+                                              const gd::String& smallicon_) override;

  /**
   * Declare a new action as being part of the behavior.
@@ -102,7 +104,7 @@ class GD_CORE_API BehaviorMetadata {
                                           const gd::String& sentence_,
                                           const gd::String& group_,
                                           const gd::String& icon_,
-                                           const gd::String& smallicon_);
+                                           const gd::String& smallicon_) override;
  /**
   * Declare a new action as being part of the extension.
   */
@@ -110,7 +112,7 @@ class GD_CORE_API BehaviorMetadata {
                                        const gd::String& fullname_,
                                        const gd::String& description_,
                                        const gd::String& group_,
-                                        const gd::String& smallicon_);
+                                        const gd::String& smallicon_) override;

  /**
   * Declare a new string expression as being part of the extension.
@@ -119,7 +121,7 @@ class GD_CORE_API BehaviorMetadata {
                                           const gd::String& fullname_,
                                           const gd::String& description_,
                                           const gd::String& group_,
-                                           const gd::String& smallicon_);
+                                           const gd::String& smallicon_) override;

  /**
   * \brief Declare a new expression and condition as being part of the
@@ -134,7 +136,7 @@ class GD_CORE_API BehaviorMetadata {
      const gd::String& description,
      const gd::String& sentenceName,
      const gd::String& group,
-      const gd::String& icon);
+      const gd::String& icon) override;

  /**
   * \brief Declare a new expression, condition and action as being part of the
@@ -151,7 +153,7 @@ class GD_CORE_API BehaviorMetadata {
      const gd::String& description,
      const gd::String& sentenceName,
      const gd::String& group,
-      const gd::String& icon);
+      const gd::String& icon) override;

  /**
   * \brief Create a new action which is the duplicate of the specified one.
@@ -160,7 +162,7 @@ class GD_CORE_API BehaviorMetadata {
   * one.
   */
  gd::InstructionMetadata& AddDuplicatedAction(
-      const gd::String& newActionName, const gd::String& copiedActionName);
+      const gd::String& newActionName, const gd::String& copiedActionName) override;

  /**
   * \brief Create a new condition which is the duplicate of the specified one.
@@ -170,7 +172,7 @@ class GD_CORE_API BehaviorMetadata {
   */
  gd::InstructionMetadata& AddDuplicatedCondition(
      const gd::String& newConditionName,
-      const gd::String& copiedConditionName);
+      const gd::String& copiedConditionName) override;

  /**
   * \brief Create a new expression which is the duplicate of the specified one.
@@ -193,9 +195,9 @@ class GD_CORE_API BehaviorMetadata {
      const gd::String& newExpressionName,
      const gd::String& copiedExpressionName);

-  BehaviorMetadata& SetFullName(const gd::String& fullname_);
+  BehaviorMetadata& SetFullName(const gd::String& fullname_) override;
  BehaviorMetadata& SetDefaultName(const gd::String& defaultName_);
-  BehaviorMetadata& SetDescription(const gd::String& description_);
+  BehaviorMetadata& SetDescription(const gd::String& description_) override;
  BehaviorMetadata& SetGroup(const gd::String& group_);

  /**
@@ -203,12 +205,12 @@ class GD_CORE_API BehaviorMetadata {
   * \note The requirement may vary depending on the platform: Most of the time,
   * the include file contains the declaration of the behavior.
   */
-  BehaviorMetadata& SetIncludeFile(const gd::String& includeFile);
+  BehaviorMetadata& SetIncludeFile(const gd::String& includeFile) override;

  /**
   * \brief Add a file to the already existing include files.
   */
-  BehaviorMetadata& AddIncludeFile(const gd::String& includeFile);
+  BehaviorMetadata& AddIncludeFile(const gd::String& includeFile) override;

  /**
   * \brief Add a file to the already existing required files.
@@ -221,7 +223,7 @@ class GD_CORE_API BehaviorMetadata {
   * Get the help path of the behavior, relative to the GDevelop documentation
   * root.
   */
-  const gd::String& GetHelpPath() const { return helpPath; }
+  const gd::String& GetHelpPath() const override { return helpPath; }

  /**
   * Set the help path of the behavior, relative to the GDevelop documentation
@@ -230,17 +232,17 @@ class GD_CORE_API BehaviorMetadata {
   * The behavior instructions will have this help path set by
   * default, unless you call SetHelpPath on them.
   */
-  BehaviorMetadata& SetHelpPath(const gd::String& path) {
+  BehaviorMetadata& SetHelpPath(const gd::String& path) override {
    helpPath = path;
    return *this;
  }

-  const gd::String& GetName() const;
-  const gd::String& GetFullName() const { return fullname; }
+  const gd::String& GetName() const override;
+  const gd::String& GetFullName() const override { return fullname; }
  const gd::String& GetDefaultName() const { return defaultName; }
-  const gd::String& GetDescription() const { return description; }
+  const gd::String& GetDescription() const override { return description; }
  const gd::String& GetGroup() const { return group; }
-  const gd::String& GetIconFilename() const { return iconFilename; }
+  const gd::String& GetIconFilename() const override { return iconFilename; }

  /**
   * \brief Set the type of the object that this behavior can be used on.
@@ -257,6 +259,11 @@ class GD_CORE_API BehaviorMetadata {
   */
  const gd::String& GetObjectType() const { return objectType; }

+  /**
+   * \brief Get the types of the behaviors that are required by this behavior.
+   */
+  const std::vector<gd::String>& GetRequiredBehaviorTypes() const;
+
  /**
   * Check if the behavior is private - it can't be used outside of its
   * extension.
@@ -272,6 +279,21 @@ class GD_CORE_API BehaviorMetadata {
    return *this;
  }

+  /**
+   * Check if the behavior is hidden - it can be used but not attached to
+   * objects by users.
+   */
+  bool IsHidden() const { return isHidden; }
+
+  /**
+   * Set that the behavior is hidden - it can be used but not attached to
+   * objects by users.
+   */
+  BehaviorMetadata &SetHidden() {
+    isHidden = true;
+    return *this;
+  }
+
  /**
   * \brief Return the associated gd::Behavior, handling behavior contents.
   * 
@@ -293,22 +315,22 @@ class GD_CORE_API BehaviorMetadata {
   * \brief Return a reference to a map containing the names of the actions
   * (as keys) and the metadata associated with (as values).
   */
-  std::map<gd::String, gd::InstructionMetadata>& GetAllActions() { return actionsInfos; };
+  std::map<gd::String, gd::InstructionMetadata>& GetAllActions() override { return actionsInfos; };

  /**
   * \see gd::PlatformExtension::GetAllActions
   */
-  std::map<gd::String, gd::InstructionMetadata>& GetAllConditions() { return conditionsInfos; };
+  std::map<gd::String, gd::InstructionMetadata>& GetAllConditions() override { return conditionsInfos; };

  /**
   * \see gd::PlatformExtension::GetAllActions
   */
-  std::map<gd::String, gd::ExpressionMetadata>& GetAllExpressions() { return expressionsInfos; };
+  std::map<gd::String, gd::ExpressionMetadata>& GetAllExpressions() override { return expressionsInfos; };

  /**
   * \see gd::PlatformExtension::GetAllActions
   */
-  std::map<gd::String, gd::ExpressionMetadata>& GetAllStrExpressions() { return strExpressionsInfos; };
+  std::map<gd::String, gd::ExpressionMetadata>& GetAllStrExpressions() override { return strExpressionsInfos; };

  std::map<gd::String, gd::InstructionMetadata> conditionsInfos;
  std::map<gd::String, gd::InstructionMetadata> actionsInfos;
@@ -328,14 +350,13 @@ class GD_CORE_API BehaviorMetadata {
  gd::String group;
  gd::String iconFilename;
  gd::String objectType;
+  mutable std::vector<gd::String> requiredBehaviors;
  bool isPrivate = false;
+  bool isHidden = false;

  // TODO: Nitpicking: convert these to std::unique_ptr to clarify ownership.
  std::shared_ptr<gd::Behavior> instance;
  std::shared_ptr<gd::BehaviorsSharedData> sharedDatasInstance;
-  bool isEventBased;
 };

 }  // namespace gd
-
-#endif  // BEHAVIORMETADATA_H
--- a/Core/GDCore/Extensions/Metadata/ExpressionMetadata.h
+++ b/Core/GDCore/Extensions/Metadata/ExpressionMetadata.h
@@ -3,9 +3,10 @@
 * Copyright 2008-2016 Florian Rival (Florian.Rival@gmail.com). All rights
 * reserved. This project is released under the MIT License.
 */
-#ifndef EXPRESSIONMETADATA_H
-#define EXPRESSIONMETADATA_H
-#if defined(GD_IDE_ONLY)
+#pragma once
+
+#include "AbstractFunctionMetadata.h"
+
 #include <functional>
 #include <memory>

@@ -17,7 +18,6 @@ class Layout;
 }

 namespace gd {
-
 /**
 * \brief Information about how generate code for an expression
 */
@@ -27,79 +27,7 @@ class ExpressionCodeGenerationInformation {
      : staticFunction(false), hasCustomCodeGenerator(false){};
  virtual ~ExpressionCodeGenerationInformation(){};

-  /**
-   * \brief Set the function name which will be used when generating the code.
-   * \param functionName the name of the function to call
-   */
-  ExpressionCodeGenerationInformation& SetFunctionName(
-      const gd::String& functionName) {
-    functionCallName = functionName;
-    return *this;
-  }
-
-  /**
-   * \brief Set that the function is static
-   */
-  ExpressionCodeGenerationInformation& SetStatic() {
-    staticFunction = true;
-    return *this;
-  }
-
-  /**
-   * \brief Erase any existing include file and add the specified include.
-   */
-  ExpressionCodeGenerationInformation& SetIncludeFile(
-      const gd::String& includeFile) {
-    includeFiles.clear();
-    includeFiles.push_back(includeFile);
-    return *this;
-  }
-
-  /**
-   * \brief Add a file to the already existing include files.
-   */
-  ExpressionCodeGenerationInformation& AddIncludeFile(
-      const gd::String& includeFile) {
-    if (std::find(includeFiles.begin(), includeFiles.end(), includeFile) ==
-        includeFiles.end())
-      includeFiles.push_back(includeFile);
-
-    return *this;
-  }
-
-  /**
-   * \brief Get the files that must be included to use the instruction.
-   */
-  const std::vector<gd::String>& GetIncludeFiles() const {
-    return includeFiles;
-  };
-
-  /**
-   * \brief Set that the function must be generated using a custom code
-   * generator.
-   */
-  ExpressionCodeGenerationInformation& SetCustomCodeGenerator(
-      std::function<gd::String(const std::vector<gd::Expression>& parameters,
-                               gd::EventsCodeGenerator& codeGenerator,
-                               gd::EventsCodeGenerationContext& context)>
-          codeGenerator) {
-    hasCustomCodeGenerator = true;
-    customCodeGenerator = codeGenerator;
-    return *this;
-  }
-
-  ExpressionCodeGenerationInformation& RemoveCustomCodeGenerator() {
-    hasCustomCodeGenerator = false;
-    std::function<gd::String(const std::vector<gd::Expression>& parameters,
-                             gd::EventsCodeGenerator& codeGenerator,
-                             gd::EventsCodeGenerationContext& context)>
-        emptyFunction;
-    customCodeGenerator = emptyFunction;
-    return *this;
-  }
-
-  bool HasCustomCodeGenerator() const { return hasCustomCodeGenerator; }
-
+  // TODO Move these attributes to ExpressionMetadata.
  bool staticFunction;
  gd::String functionCallName;
  bool hasCustomCodeGenerator;
@@ -107,8 +35,6 @@ class ExpressionCodeGenerationInformation {
                           gd::EventsCodeGenerator& codeGenerator,
                           gd::EventsCodeGenerationContext& context)>
      customCodeGenerator;
-
- private:
  std::vector<gd::String> includeFiles;
 };

@@ -118,7 +44,7 @@ class ExpressionCodeGenerationInformation {
 *
 * \ingroup Events
 */
-class GD_CORE_API ExpressionMetadata {
+class GD_CORE_API ExpressionMetadata : public gd::AbstractFunctionMetadata {
 public:
  /**
   * Construct a new expression metadata.
@@ -144,7 +70,7 @@ class GD_CORE_API ExpressionMetadata {
  /**
   * \brief Set the expression as not shown in the IDE.
   */
-  ExpressionMetadata& SetHidden();
+  ExpressionMetadata& SetHidden() override;

  /**
   * \brief Set the group of the instruction in the IDE.
@@ -179,7 +105,7 @@ class GD_CORE_API ExpressionMetadata {
   * Set that the instruction is private - it can't be used outside of the
   * object/ behavior that it is attached too.
   */
-  ExpressionMetadata& SetPrivate() {
+  ExpressionMetadata& SetPrivate() override {
    isPrivate = true;
    return *this;
  }
@@ -216,7 +142,7 @@ class GD_CORE_API ExpressionMetadata {
  /**
   * Set that the instruction can be used in layouts or external events.
   */
-  ExpressionMetadata &SetRelevantForLayoutEventsOnly() {
+  ExpressionMetadata &SetRelevantForLayoutEventsOnly() override {
    relevantContext = "Layout";
    return *this;
  }
@@ -224,7 +150,7 @@ class GD_CORE_API ExpressionMetadata {
  /**
   * Set that the instruction can be used in function events.
   */
-  ExpressionMetadata &SetRelevantForFunctionEventsOnly() {
+  ExpressionMetadata &SetRelevantForFunctionEventsOnly() override {
    relevantContext = "Function";
    return *this;
  }
@@ -232,7 +158,7 @@ class GD_CORE_API ExpressionMetadata {
  /**
   * Set that the instruction can be used in asynchronous function events.
   */
-  ExpressionMetadata &SetRelevantForAsynchronousFunctionEventsOnly() {
+  ExpressionMetadata &SetRelevantForAsynchronousFunctionEventsOnly() override {
    relevantContext = "AsynchronousFunction";
    return *this;
  }
@@ -240,7 +166,7 @@ class GD_CORE_API ExpressionMetadata {
  /**
   * Set that the instruction can be used in custom object events.
   */
-  ExpressionMetadata &SetRelevantForCustomObjectEventsOnly() {
+  ExpressionMetadata &SetRelevantForCustomObjectEventsOnly() override {
    relevantContext = "Object";
    return *this;
  }
@@ -248,17 +174,17 @@ class GD_CORE_API ExpressionMetadata {
  /**
   * \see gd::InstructionMetadata::AddParameter
   */
-  gd::ExpressionMetadata& AddParameter(
-      const gd::String& type,
-      const gd::String& description,
-      const gd::String& supplementaryInformation = "",
-      bool parameterIsOptional = false);
+  gd::ExpressionMetadata &
+  AddParameter(const gd::String &type, const gd::String &label,
+               const gd::String &supplementaryInformation = "",
+               bool parameterIsOptional = false) override;

  /**
   * \see gd::InstructionMetadata::AddCodeOnlyParameter
   */
-  gd::ExpressionMetadata& AddCodeOnlyParameter(
-      const gd::String& type, const gd::String& supplementaryInformation);
+  gd::ExpressionMetadata &
+  AddCodeOnlyParameter(const gd::String &type,
+                       const gd::String &supplementaryInformation) override;

  /**
   * Set the default value used in editor (or if an optional parameter is empty
@@ -266,8 +192,9 @@ class GD_CORE_API ExpressionMetadata {
   *
   * \see AddParameter
   */
-  ExpressionMetadata& SetDefaultValue(gd::String defaultValue_) {
-    if (!parameters.empty()) parameters.back().SetDefaultValue(defaultValue_);
+  ExpressionMetadata &SetDefaultValue(const gd::String &defaultValue) override {
+    if (!parameters.empty())
+      parameters.back().SetDefaultValue(defaultValue);
    return *this;
  };

@@ -277,7 +204,8 @@ class GD_CORE_API ExpressionMetadata {
   *
   * \see AddParameter
   */
-  ExpressionMetadata& SetParameterLongDescription(gd::String longDescription) {
+  ExpressionMetadata &
+  SetParameterLongDescription(const gd::String &longDescription) override {
    if (!parameters.empty())
      parameters.back().SetLongDescription(longDescription);
    return *this;
@@ -290,7 +218,8 @@ class GD_CORE_API ExpressionMetadata {
   *
   * \see AddParameter
   */
-  ExpressionMetadata &SetParameterExtraInfo(const gd::String &extraInfo) {
+  ExpressionMetadata &SetParameterExtraInfo(
+      const gd::String &extraInfo) override {
    if (!parameters.empty()) parameters.back().SetExtraInfo(extraInfo);
    return *this;
  }
@@ -312,50 +241,6 @@ class GD_CORE_API ExpressionMetadata {
    return requiredBaseObjectCapability;
  };

-  /**
-   * \brief Set the function that should be called when generating the source
-   * code from events.
-   * \param functionName the name of the function to call
-   * \note Shortcut for `codeExtraInformation.SetFunctionName`.
-   */
-  ExpressionCodeGenerationInformation& SetFunctionName(
-      const gd::String& functionName) {
-    return codeExtraInformation.SetFunctionName(functionName);
-  }
-
-  /**
-   * \brief Return the structure containing the information about code
-   * generation for the expression.
-   */
-  ExpressionCodeGenerationInformation& GetCodeExtraInformation() {
-    return codeExtraInformation;
-  }
-
-  /**
-   * \brief Erase any existing include file and add the specified include.
-   */
-  ExpressionMetadata &SetIncludeFile(const gd::String &includeFile) {
-    codeExtraInformation.SetIncludeFile(includeFile);
-    return *this;
-  }
-
-  /**
-   * \brief Add a file to the already existing include files.
-   */
-  ExpressionMetadata &AddIncludeFile(const gd::String &includeFile) {
-    codeExtraInformation.AddIncludeFile(includeFile);
-    return *this;
-  }
-
-  /**
-   * \brief Get the files that must be included to use the instruction.
-   */
-  const std::vector<gd::String>& GetIncludeFiles() const {
-    return codeExtraInformation.GetIncludeFiles();
-  }
-
-  ExpressionCodeGenerationInformation codeExtraInformation;
-
  bool IsShown() const { return shown; }
  const gd::String& GetReturnType() const { return returnType; }
  const gd::String& GetFullName() const { return fullname; }
@@ -375,6 +260,99 @@ class GD_CORE_API ExpressionMetadata {

  std::vector<gd::ParameterMetadata> parameters;

+  
+  /**
+   * \brief Set the function name which will be used when generating the code.
+   * \param functionName the name of the function to call
+   */
+  ExpressionMetadata& SetFunctionName(
+      const gd::String& functionName) override {
+    codeExtraInformation.functionCallName = functionName;
+    return *this;
+  }
+
+
+  /**
+   * \brief Return the name of the function which will be called in the generated code.
+   */
+  const gd::String &GetFunctionName() {
+    return codeExtraInformation.functionCallName;
+  }
+  /**
+   * \brief Set that the function is static
+   */
+  ExpressionMetadata& SetStatic() {
+    codeExtraInformation.staticFunction = true;
+    return *this;
+  }
+
+  /**
+   * \brief Erase any existing include file and add the specified include.
+   */
+  ExpressionMetadata& SetIncludeFile(
+      const gd::String& includeFile) override {
+    codeExtraInformation.includeFiles.clear();
+    codeExtraInformation.includeFiles.push_back(includeFile);
+    return *this;
+  }
+
+  /**
+   * \brief Add a file to the already existing include files.
+   */
+  ExpressionMetadata& AddIncludeFile(
+      const gd::String& includeFile) override {
+    if (std::find(codeExtraInformation.includeFiles.begin(), codeExtraInformation.includeFiles.end(), includeFile) ==
+        codeExtraInformation.includeFiles.end())
+      codeExtraInformation.includeFiles.push_back(includeFile);
+
+    return *this;
+  }
+
+  /**
+   * \brief Get the files that must be included to use the instruction.
+   */
+  const std::vector<gd::String>& GetIncludeFiles() const override {
+    return codeExtraInformation.includeFiles;
+  };
+
+  /**
+   * \brief Set that the function must be generated using a custom code
+   * generator.
+   */
+  ExpressionMetadata& SetCustomCodeGenerator(
+      std::function<gd::String(const std::vector<gd::Expression>& parameters,
+                               gd::EventsCodeGenerator& codeGenerator,
+                               gd::EventsCodeGenerationContext& context)>
+          codeGenerator) {
+    codeExtraInformation.hasCustomCodeGenerator = true;
+    codeExtraInformation.customCodeGenerator = codeGenerator;
+    return *this;
+  }
+
+  ExpressionMetadata& RemoveCustomCodeGenerator() {
+    codeExtraInformation.hasCustomCodeGenerator = false;
+    std::function<gd::String(const std::vector<gd::Expression>& parameters,
+                             gd::EventsCodeGenerator& codeGenerator,
+                             gd::EventsCodeGenerationContext& context)>
+        emptyFunction;
+    codeExtraInformation.customCodeGenerator = emptyFunction;
+    return *this;
+  }
+
+  bool HasCustomCodeGenerator() const { return codeExtraInformation.hasCustomCodeGenerator; }
+
+  /**
+   * \brief Return the structure containing the information about code
+   * generation for the expression.
+   * 
+   * \deprecated
+   */
+  ExpressionMetadata& GetCodeExtraInformation() {
+    return *this;
+  }
+
+  ExpressionCodeGenerationInformation codeExtraInformation;
+
 private:
  gd::String returnType;
  gd::String fullname;
@@ -391,6 +369,3 @@ class GD_CORE_API ExpressionMetadata {
 };

 }  // namespace gd
-
-#endif
-#endif  // EXPRESSIONMETADATA_H
--- a/Core/GDCore/Extensions/Metadata/InstructionMetadata.h
+++ b/Core/GDCore/Extensions/Metadata/InstructionMetadata.h
@@ -4,8 +4,10 @@
 * reserved. This project is released under the MIT License.
 */

-#ifndef INSTRUCTIONMETADATA_H
-#define INSTRUCTIONMETADATA_H
+#pragma once
+
+#include "AbstractFunctionMetadata.h"
+
 #include <algorithm>
 #include <functional>
 #include <map>
@@ -33,7 +35,7 @@ namespace gd {
 *
 * \ingroup Events
 */
-class GD_CORE_API InstructionMetadata {
+class GD_CORE_API InstructionMetadata : public gd::AbstractFunctionMetadata {
 public:
  /**
   * Construct a new instruction metadata.
@@ -96,7 +98,7 @@ class GD_CORE_API InstructionMetadata {
   * Set that the instruction is private - it can't be used outside of the
   * object/ behavior that it is attached too.
   */
-  InstructionMetadata &SetPrivate() {
+  InstructionMetadata &SetPrivate() override {
    isPrivate = true;
    return *this;
  }
@@ -133,7 +135,7 @@ class GD_CORE_API InstructionMetadata {
  /**
   * Set that the instruction can be used in layouts or external events.
   */
-  InstructionMetadata &SetRelevantForLayoutEventsOnly() {
+  InstructionMetadata &SetRelevantForLayoutEventsOnly() override {
    relevantContext = "Layout";
    return *this;
  }
@@ -141,7 +143,7 @@ class GD_CORE_API InstructionMetadata {
  /**
   * Set that the instruction can be used in function events.
   */
-  InstructionMetadata &SetRelevantForFunctionEventsOnly() {
+  InstructionMetadata &SetRelevantForFunctionEventsOnly() override {
    relevantContext = "Function";
    return *this;
  }
@@ -149,7 +151,7 @@ class GD_CORE_API InstructionMetadata {
  /**
   * Set that the instruction can be used in asynchronous function events.
   */
-  InstructionMetadata &SetRelevantForAsynchronousFunctionEventsOnly() {
+  InstructionMetadata &SetRelevantForAsynchronousFunctionEventsOnly() override {
    relevantContext = "AsynchronousFunction";
    return *this;
  }
@@ -157,7 +159,7 @@ class GD_CORE_API InstructionMetadata {
  /**
   * Set that the instruction can be used in custom object events.
   */
-  InstructionMetadata &SetRelevantForCustomObjectEventsOnly() {
+  InstructionMetadata &SetRelevantForCustomObjectEventsOnly() override {
    relevantContext = "Object";
    return *this;
  }
@@ -192,7 +194,7 @@ class GD_CORE_API InstructionMetadata {
   *
   * Used mainly when an instruction is deprecated.
   */
-  InstructionMetadata &SetHidden() {
+  InstructionMetadata &SetHidden() override {
    hidden = true;
    return *this;
  }
@@ -231,7 +233,7 @@ class GD_CORE_API InstructionMetadata {
      const gd::String &type,
      const gd::String &label,
      const gd::String &supplementaryInformation = "",
-      bool parameterIsOptional = false);
+      bool parameterIsOptional = false) override;

  /**
   * \brief Add a parameter not displayed in editor.
@@ -245,7 +247,7 @@ class GD_CORE_API InstructionMetadata {
   * \see EventsCodeGenerator::GenerateParametersCodes
   */
  InstructionMetadata &AddCodeOnlyParameter(
-      const gd::String &type, const gd::String &supplementaryInformation);
+      const gd::String &type, const gd::String &supplementaryInformation) override;

  /**
   * \brief Set the default value used in editor (or if an optional parameter is
@@ -253,7 +255,7 @@ class GD_CORE_API InstructionMetadata {
   *
   * \see AddParameter
   */
-  InstructionMetadata &SetDefaultValue(const gd::String &defaultValue_) {
+  InstructionMetadata &SetDefaultValue(const gd::String &defaultValue_) override {
    if (!parameters.empty()) parameters.back().SetDefaultValue(defaultValue_);
    return *this;
  };
@@ -265,7 +267,7 @@ class GD_CORE_API InstructionMetadata {
   * \see AddParameter
   */
  InstructionMetadata &SetParameterLongDescription(
-      const gd::String &longDescription) {
+      const gd::String &longDescription) override {
    if (!parameters.empty())
      parameters.back().SetLongDescription(longDescription);
    return *this;
@@ -278,7 +280,7 @@ class GD_CORE_API InstructionMetadata {
   *
   * \see AddParameter
   */
-  InstructionMetadata &SetParameterExtraInfo(const gd::String &extraInfo) {
+  InstructionMetadata &SetParameterExtraInfo(const gd::String &extraInfo) override {
    if (!parameters.empty()) parameters.back().SetExtraInfo(extraInfo);
    return *this;
  }
@@ -382,128 +384,13 @@ class GD_CORE_API InstructionMetadata {
  /**
   * \brief Defines information about how generate the code for an instruction
   */
-  class ExtraInformation {
+  class ExtraInformation { 
   public:
    enum AccessType { Reference, MutatorAndOrAccessor, Mutators };
    ExtraInformation() : accessType(Reference), hasCustomCodeGenerator(false){};
    virtual ~ExtraInformation(){};

-    /**
-     * Set the name of the function which will be called in the generated code.
-     * \param functionName the name of the function to call.
-     */
-    ExtraInformation &SetFunctionName(const gd::String &functionName_) {
-      functionCallName = functionName_;
-      return *this;
-    }
-
-    /**
-     * Set the name of the function, doing asynchronous work, which will be
-     * called in the generated code. This function should return an asynchronous
-     * task (i.e: `gdjs.AsyncTask` in the JavaScript runtime).
-     *
-     * \param functionName the name of the function doing asynchronous work to
-     * call.
-     */
-    ExtraInformation &SetAsyncFunctionName(const gd::String &functionName_) {
-      asyncFunctionCallName = functionName_;
-      return *this;
-    }
-
-    /**
-     * Declare if the instruction being declared is somewhat manipulating in a
-     * standard way.
-     */
-    ExtraInformation &SetManipulatedType(const gd::String &type_) {
-      type = type_;
-      return *this;
-    }
-
-    /**
-     * If InstructionMetadata::ExtraInformation::SetManipulatedType was called
-     * with "number" or "string", this function will tell the code generator the
-     * name of the getter function used to retrieve the data value.
-     *
-     * Usage example:
-     * \code
-     *  obj.AddAction("String",
-     *                 _("Change the string"),
-     *                 _("Change the string of a text"),
-     *                 _("the string"),
-     *                 _("Text"),
-     *                 "CppPlatform/Extensions/text24.png",
-     *                 "CppPlatform/Extensions/text_black.png");
-     *
-     *      .AddParameter("object", _("Object"), "Text", false)
-     *      .AddParameter("operator", _("Modification operator"), "string")
-     *      .AddParameter("string", _("String"))
-     *      .SetFunctionName("SetString").SetManipulatedType("string").SetGetter("GetString");
-     *
-     *  DECLARE_END_OBJECT_ACTION()
-     * \endcode
-     */
-    ExtraInformation &SetGetter(const gd::String &getter) {
-      optionalAssociatedInstruction = getter;
-      accessType = MutatorAndOrAccessor;
-      return *this;
-    }
-
-    ExtraInformation &SetMutators(
-        const std::map<gd::String, gd::String> &mutators) {
-      optionalMutators = mutators;
-      accessType = Mutators;
-      return *this;
-    }
-
-    /**
-     * \brief Erase any existing include file and add the specified include.
-     */
-    ExtraInformation &SetIncludeFile(const gd::String &includeFile) {
-      includeFiles.clear();
-      includeFiles.push_back(includeFile);
-      return *this;
-    }
-
-    /**
-     * \brief Add a file to the already existing include files.
-     */
-    ExtraInformation &AddIncludeFile(const gd::String &includeFile) {
-      if (std::find(includeFiles.begin(), includeFiles.end(), includeFile) ==
-          includeFiles.end())
-        includeFiles.push_back(includeFile);
-
-      return *this;
-    }
-
-    /**
-     * \brief Get the files that must be included to use the instruction.
-     */
-    const std::vector<gd::String> &GetIncludeFiles() const {
-      return includeFiles;
-    };
-
-    ExtraInformation &SetCustomCodeGenerator(
-        std::function<gd::String(Instruction &instruction,
-                                 gd::EventsCodeGenerator &codeGenerator,
-                                 gd::EventsCodeGenerationContext &context)>
-            codeGenerator) {
-      hasCustomCodeGenerator = true;
-      customCodeGenerator = codeGenerator;
-      return *this;
-    }
-
-    ExtraInformation &RemoveCustomCodeGenerator() {
-      hasCustomCodeGenerator = false;
-      std::function<gd::String(Instruction & instruction,
-                               gd::EventsCodeGenerator & codeGenerator,
-                               gd::EventsCodeGenerationContext & context)>
-          emptyFunction;
-      customCodeGenerator = emptyFunction;
-      return *this;
-    }
-
-    bool HasCustomCodeGenerator() const { return hasCustomCodeGenerator; }
-
+    // TODO Move these attributes to InstructionMetadata.
    gd::String functionCallName;
    gd::String asyncFunctionCallName;
    gd::String type;
@@ -512,75 +399,156 @@ class GD_CORE_API InstructionMetadata {
    std::map<gd::String, gd::String> optionalMutators;
    bool hasCustomCodeGenerator;
    std::function<gd::String(Instruction &instruction,
-                             gd::EventsCodeGenerator &codeGenerator,
-                             gd::EventsCodeGenerationContext &context)>
+                              gd::EventsCodeGenerator &codeGenerator,
+                              gd::EventsCodeGenerationContext &context)>
        customCodeGenerator;
-
-   private:
    std::vector<gd::String> includeFiles;
  };
  ExtraInformation codeExtraInformation;  ///< Information about how generate
                                          ///< code for the instruction

-  /**
-   * \brief Return the structure containing the information about code
-   * generation for the instruction.
-   */
-  ExtraInformation &GetCodeExtraInformation() { return codeExtraInformation; }
-
-  /**
-   * \brief Declare if the instruction being declared is somewhat manipulating
-   * in a standard way. \param type "number" or "string" \note Shortcut for
-   * `codeExtraInformation.SetManipulatedType(type)`.
-   */
-  ExtraInformation &SetManipulatedType(const gd::String &type_) {
-    return codeExtraInformation.SetManipulatedType(type_);
-  }
-
  /**
   * Set the name of the function which will be called in the generated code.
   * \param functionName the name of the function to call.
-   * \note Shortcut for `codeExtraInformation.SetFunctionName`.
   */
-  ExtraInformation &SetFunctionName(const gd::String &functionName) {
-    return codeExtraInformation.SetFunctionName(functionName);
+  InstructionMetadata &SetFunctionName(const gd::String &functionName_) override {
+    codeExtraInformation.functionCallName = functionName_;
+    return *this;
  }

  /**
-   * Set the name of the function, doing asynchronous work, which will be called
-   * in the generated code. This function should return an asynchronous task
-   * (i.e: `gdjs.AsyncTask` in the JavaScript runtime).
+   * Set the name of the function, doing asynchronous work, which will be
+   * called in the generated code. This function should return an asynchronous
+   * task (i.e: `gdjs.AsyncTask` in the JavaScript runtime).
   *
   * \param functionName the name of the function doing asynchronous work to
-   * call. \note Shortcut for `codeExtraInformation.SetAsyncFunctionName`.
+   * call.
   */
-  ExtraInformation &SetAsyncFunctionName(const gd::String &functionName) {
-    return codeExtraInformation.SetAsyncFunctionName(functionName);
+  InstructionMetadata &SetAsyncFunctionName(const gd::String &functionName_) {
+    codeExtraInformation.asyncFunctionCallName = functionName_;
+    return *this;
+  }
+
+  /**
+   * Return the name of the function which will be called in the generated code.
+   */
+  const gd::String &GetFunctionName() {
+    return codeExtraInformation.functionCallName;
+  }
+
+  /**
+   * Return the name of the function, doing asynchronous work, which will be
+   * called in the generated code. This function should return an asynchronous
+   * task (i.e: `gdjs.AsyncTask` in the JavaScript runtime).
+   */
+  const gd::String &GetAsyncFunctionName() {
+    return codeExtraInformation.asyncFunctionCallName;
+  }
+
+/**
+ * \brief Declare if the instruction being declared is somewhat manipulating
+ * in a standard way.
+ * 
+ * \param type "number" or "string"
+ */
+  InstructionMetadata &SetManipulatedType(const gd::String &type_) {
+    codeExtraInformation.type = type_;
+    return *this;
+  }
+
+  /**
+   * If InstructionMetadata::ExtraInformation::SetManipulatedType was called
+   * with "number" or "string", this function will tell the code generator the
+   * name of the getter function used to retrieve the data value.
+   *
+   * Usage example:
+   * \code
+   *  obj.AddAction("String",
+   *                 _("Change the string"),
+   *                 _("Change the string of a text"),
+   *                 _("the string"),
+   *                 _("Text"),
+   *                 "CppPlatform/Extensions/text24.png",
+   *                 "CppPlatform/Extensions/text_black.png");
+   *
+   *      .AddParameter("object", _("Object"), "Text", false)
+   *      .AddParameter("operator", _("Modification operator"), "string")
+   *      .AddParameter("string", _("String"))
+   *      .SetFunctionName("SetString").SetManipulatedType("string").SetGetter("GetString");
+   *
+   *  DECLARE_END_OBJECT_ACTION()
+   * \endcode
+   */
+  InstructionMetadata &SetGetter(const gd::String &getter) {
+    codeExtraInformation.optionalAssociatedInstruction = getter;
+    codeExtraInformation.accessType = codeExtraInformation.MutatorAndOrAccessor;
+    return *this;
+  }
+
+  InstructionMetadata &SetMutators(
+      const std::map<gd::String, gd::String> &mutators) {
+    codeExtraInformation.optionalMutators = mutators;
+    codeExtraInformation.accessType = codeExtraInformation.Mutators;
+    return *this;
  }

  /**
   * \brief Erase any existing include file and add the specified include.
   */
-  InstructionMetadata &SetIncludeFile(const gd::String &includeFile) {
-    codeExtraInformation.SetIncludeFile(includeFile);
+  InstructionMetadata &SetIncludeFile(const gd::String &includeFile) override {
+    codeExtraInformation.includeFiles.clear();
+    codeExtraInformation.includeFiles.push_back(includeFile);
    return *this;
  }

  /**
   * \brief Add a file to the already existing include files.
   */
-  InstructionMetadata &AddIncludeFile(const gd::String &includeFile) {
-    codeExtraInformation.AddIncludeFile(includeFile);
+  InstructionMetadata &AddIncludeFile(const gd::String &includeFile) override {
+    if (std::find(codeExtraInformation.includeFiles.begin(), codeExtraInformation.includeFiles.end(), includeFile) ==
+        codeExtraInformation.includeFiles.end())
+      codeExtraInformation.includeFiles.push_back(includeFile);
+
    return *this;
  }

  /**
   * \brief Get the files that must be included to use the instruction.
   */
-  const std::vector<gd::String> &GetIncludeFiles() const {
-    return codeExtraInformation.GetIncludeFiles();
+  const std::vector<gd::String> &GetIncludeFiles() const override {
+    return codeExtraInformation.includeFiles;
  };

+  InstructionMetadata &SetCustomCodeGenerator(
+      std::function<gd::String(Instruction &instruction,
+                                gd::EventsCodeGenerator &codeGenerator,
+                                gd::EventsCodeGenerationContext &context)>
+          codeGenerator) {
+    codeExtraInformation.hasCustomCodeGenerator = true;
+    codeExtraInformation.customCodeGenerator = codeGenerator;
+    return *this;
+  }
+
+  InstructionMetadata &RemoveCustomCodeGenerator() {
+    codeExtraInformation.hasCustomCodeGenerator = false;
+    std::function<gd::String(Instruction & instruction,
+                              gd::EventsCodeGenerator & codeGenerator,
+                              gd::EventsCodeGenerationContext & context)>
+        emptyFunction;
+    codeExtraInformation.customCodeGenerator = emptyFunction;
+    return *this;
+  }
+
+  bool HasCustomCodeGenerator() const { return codeExtraInformation.hasCustomCodeGenerator; }
+
+  /**
+   * \brief Return the structure containing the information about code
+   * generation for the instruction.
+   * 
+   * \deprecated
+   */
+  InstructionMetadata &GetCodeExtraInformation() { return *this; }
+
  std::vector<ParameterMetadata> parameters;

 private:
@@ -604,5 +572,3 @@ class GD_CORE_API InstructionMetadata {
 };

 }  // namespace gd
-
-#endif  // INSTRUCTIONMETADATA_H
--- a/Core/GDCore/Extensions/Metadata/InstructionOrExpressionContainerMetadata.h
+++ b/Core/GDCore/Extensions/Metadata/InstructionOrExpressionContainerMetadata.h
@@ -0,0 +1,201 @@
+/*
+ * GDevelop Core
+ * Copyright 2008-2016 Florian Rival (Florian.Rival@gmail.com). All rights
+ * reserved. This project is released under the MIT License.
+ */
+#pragma once
+
+#include <map>
+
+#include "GDCore/Extensions/Metadata/ExpressionMetadata.h"
+#include "GDCore/Extensions/Metadata/InstructionMetadata.h"
+#include "GDCore/String.h"
+
+namespace gd {
+class Behavior;
+class BehaviorsSharedData;
+class MultipleInstructionMetadata;
+class InstructionMetadata;
+class ExpressionMetadata;
+} // namespace gd
+
+namespace gd {
+
+/**
+ * \brief Contains user-friendly information about instructions and expressions
+ * (usually for a behavior or an object).
+ *
+ * \ingroup Events
+ */
+class GD_CORE_API InstructionOrExpressionContainerMetadata {
+public:
+  InstructionOrExpressionContainerMetadata(){};
+  virtual ~InstructionOrExpressionContainerMetadata(){};
+
+  /**
+   * Declare a new condition as being part of the behavior or object.
+   * \deprecated Prefer using `AddScopedCondition`, to properly namespace
+   * the condition.
+   */
+  virtual gd::InstructionMetadata &
+  AddCondition(const gd::String &name_, const gd::String &fullname_,
+               const gd::String &description_, const gd::String &sentence_,
+               const gd::String &group_, const gd::String &icon_,
+               const gd::String &smallicon_) = 0;
+
+  /**
+   * Declare a new action as being part of the behavior or object.
+   * \deprecated Prefer using `AddScopedAction`, to properly namespace
+   * the action.
+   */
+  virtual gd::InstructionMetadata &
+  AddAction(const gd::String &name_, const gd::String &fullname_,
+            const gd::String &description_, const gd::String &sentence_,
+            const gd::String &group_, const gd::String &icon_,
+            const gd::String &smallicon_) = 0;
+
+  /**
+   * Declare a new condition as being part of the behavior or object.
+   */
+  virtual gd::InstructionMetadata &
+  AddScopedCondition(const gd::String &name_, const gd::String &fullname_,
+                     const gd::String &description_,
+                     const gd::String &sentence_, const gd::String &group_,
+                     const gd::String &icon_, const gd::String &smallicon_) = 0;
+
+  /**
+   * Declare a new action as being part of the behavior or object.
+   */
+  virtual gd::InstructionMetadata &
+  AddScopedAction(const gd::String &name_, const gd::String &fullname_,
+                  const gd::String &description_, const gd::String &sentence_,
+                  const gd::String &group_, const gd::String &icon_,
+                  const gd::String &smallicon_) = 0;
+  /**
+   * Declare a new action as being part of the extension.
+   */
+  virtual gd::ExpressionMetadata &
+  AddExpression(const gd::String &name_, const gd::String &fullname_,
+                const gd::String &description_, const gd::String &group_,
+                const gd::String &smallicon_) = 0;
+
+  /**
+   * Declare a new string expression as being part of the extension.
+   */
+  virtual gd::ExpressionMetadata &
+  AddStrExpression(const gd::String &name_, const gd::String &fullname_,
+                   const gd::String &description_, const gd::String &group_,
+                   const gd::String &smallicon_) = 0;
+
+  /**
+   * \brief Declare a new expression and condition as being part of the
+   * behavior.
+   * \note It's recommended to use this function to avoid declaring twice a
+   * similar expression/condition.
+   */
+  virtual gd::MultipleInstructionMetadata AddExpressionAndCondition(
+      const gd::String &type, const gd::String &name,
+      const gd::String &fullname, const gd::String &description,
+      const gd::String &sentenceName, const gd::String &group,
+      const gd::String &icon) = 0;
+
+  /**
+   * \brief Declare a new expression, condition and action as being part of the
+   * behavior.
+   * \note The action name is prefixed by "Set" (and the namespace, as the
+   * condition).
+   * \note It's recommended to use this function to avoid declaring 3 times a
+   * similar expression/condition/action.
+   */
+  virtual gd::MultipleInstructionMetadata AddExpressionAndConditionAndAction(
+      const gd::String &type, const gd::String &name,
+      const gd::String &fullname, const gd::String &description,
+      const gd::String &sentenceName, const gd::String &group,
+      const gd::String &icon) = 0;
+
+  /**
+   * \brief Create a new action which is the duplicate of the specified one.
+   *
+   * Useful for handling a deprecated action that is just a "copy" of the new
+   * one.
+   */
+  virtual gd::InstructionMetadata &
+  AddDuplicatedAction(const gd::String &newActionName,
+                      const gd::String &copiedActionName) = 0;
+
+  /**
+   * \brief Create a new condition which is the duplicate of the specified one.
+   *
+   * Useful for handling a deprecated condition that is just a "copy" of the new
+   * one.
+   */
+  virtual gd::InstructionMetadata &
+  AddDuplicatedCondition(const gd::String &newConditionName,
+                         const gd::String &copiedConditionName) = 0;
+
+  virtual InstructionOrExpressionContainerMetadata &
+  SetFullName(const gd::String &fullname_) = 0;
+  virtual InstructionOrExpressionContainerMetadata &
+  SetDescription(const gd::String &description_) = 0;
+
+  /**
+   * \brief Erase any existing include file and add the specified include.
+   * \note The requirement may vary depending on the platform: Most of the time,
+   * the include file contains the declaration of the behavior.
+   */
+  virtual InstructionOrExpressionContainerMetadata &
+  SetIncludeFile(const gd::String &includeFile) = 0;
+
+  /**
+   * \brief Add a file to the already existing include files.
+   */
+  virtual InstructionOrExpressionContainerMetadata &
+  AddIncludeFile(const gd::String &includeFile) = 0;
+
+  /**
+   * Get the help path of the behavior, relative to the GDevelop documentation
+   * root.
+   */
+  virtual const gd::String &GetHelpPath() const = 0;
+
+  /**
+   * Set the help path of the behavior, relative to the GDevelop documentation
+   * root.
+   *
+   * The behavior instructions will have this help path set by
+   * default, unless you call SetHelpPath on them.
+   */
+  virtual InstructionOrExpressionContainerMetadata &
+  SetHelpPath(const gd::String &path) = 0;
+
+  virtual const gd::String &GetName() const = 0;
+  virtual const gd::String &GetFullName() const = 0;
+  virtual const gd::String &GetDescription() const = 0;
+  virtual const gd::String &GetIconFilename() const = 0;
+
+  /**
+   * \brief Return a reference to a map containing the names of the actions
+   * (as keys) and the metadata associated with (as values).
+   */
+  virtual std::map<gd::String, gd::InstructionMetadata> &GetAllActions() = 0;
+
+  /**
+   * \see gd::PlatformExtension::GetAllActions
+   */
+  virtual std::map<gd::String, gd::InstructionMetadata> &GetAllConditions() = 0;
+
+  /**
+   * \see gd::PlatformExtension::GetAllActions
+   */
+  virtual std::map<gd::String, gd::ExpressionMetadata> &GetAllExpressions() = 0;
+
+  /**
+   * \see gd::PlatformExtension::GetAllActions
+   */
+  virtual std::map<gd::String, gd::ExpressionMetadata> &
+  GetAllStrExpressions() = 0;
+
+private:
+};
+
+} // namespace gd
--- a/Core/GDCore/Extensions/Metadata/MetadataProvider.cpp
+++ b/Core/GDCore/Extensions/Metadata/MetadataProvider.cpp
@@ -135,11 +135,11 @@ MetadataProvider::GetExtensionAndConditionMetadata(const gd::Platform& platform,

    const auto& objects = extension->GetExtensionObjectsTypes();
    for (const gd::String& extObjectType : objects) {
-      const auto& allObjetsConditions =
+      const auto& allObjectsConditions =
          extension->GetAllConditionsForObject(extObjectType);
-      if (allObjetsConditions.find(conditionType) != allObjetsConditions.end())
+      if (allObjectsConditions.find(conditionType) != allObjectsConditions.end())
        return ExtensionAndMetadata<InstructionMetadata>(
-            *extension, allObjetsConditions.find(conditionType)->second);
+            *extension, allObjectsConditions.find(conditionType)->second);
    }

    const auto& autos = extension->GetBehaviorsTypes();
--- a/Core/GDCore/Extensions/Metadata/MetadataProvider.h
+++ b/Core/GDCore/Extensions/Metadata/MetadataProvider.h
@@ -275,6 +275,10 @@ class GD_CORE_API MetadataProvider {
    return &metadata == &badBehaviorMetadata;
  }

+  static bool IsBadObjectMetadata(const gd::ObjectMetadata& metadata) {
+    return &metadata == &badObjectInfo;
+  }
+
  virtual ~MetadataProvider();

 private:
--- a/Core/GDCore/Extensions/Metadata/MultipleInstructionMetadata.cpp
+++ b/Core/GDCore/Extensions/Metadata/MultipleInstructionMetadata.cpp
@@ -1,12 +0,0 @@
-/*
- * GDevelop Core
- * Copyright 2008-present Florian Rival (Florian.Rival@gmail.com). All rights
- * reserved. This project is released under the MIT License.
- */
-#include "MultipleInstructionMetadata.h"
-
-#include "InstructionMetadata.h"
-
-namespace gd {
-
-}  // namespace gd
--- a/Core/GDCore/Extensions/Metadata/MultipleInstructionMetadata.h
+++ b/Core/GDCore/Extensions/Metadata/MultipleInstructionMetadata.h
@@ -3,8 +3,8 @@
 * Copyright 2008-present Florian Rival (Florian.Rival@gmail.com). All rights
 * reserved. This project is released under the MIT License.
 */
-#ifndef MULTIPLEINSTRUCTIONSMETADATA_H
-#define MULTIPLEINSTRUCTIONSMETADATA_H
+#pragma once
+
 #include "GDCore/Extensions/Metadata/ExpressionMetadata.h"
 #include "GDCore/Extensions/Metadata/InstructionMetadata.h"
 #include "GDCore/String.h"
@@ -21,7 +21,7 @@ namespace gd {
 *
 * \ingroup PlatformDefinition
 */
-class GD_CORE_API MultipleInstructionMetadata {
+class GD_CORE_API MultipleInstructionMetadata : public AbstractFunctionMetadata {
 public:
  static MultipleInstructionMetadata WithExpressionAndCondition(
      gd::ExpressionMetadata &expression, gd::InstructionMetadata &condition) {
@@ -45,7 +45,7 @@ class GD_CORE_API MultipleInstructionMetadata {
      const gd::String &type,
      const gd::String &label,
      const gd::String &supplementaryInformation = "",
-      bool parameterIsOptional = false) {
+      bool parameterIsOptional = false) override {
    if (expression)
      expression->AddParameter(
          type, label, supplementaryInformation, parameterIsOptional);
@@ -62,7 +62,7 @@ class GD_CORE_API MultipleInstructionMetadata {
   * \see gd::InstructionMetadata::AddCodeOnlyParameter
   */
  MultipleInstructionMetadata &AddCodeOnlyParameter(
-      const gd::String &type, const gd::String &supplementaryInformation) {
+      const gd::String &type, const gd::String &supplementaryInformation) override {
    if (expression)
      expression->AddCodeOnlyParameter(type, supplementaryInformation);
    if (condition)
@@ -74,7 +74,7 @@ class GD_CORE_API MultipleInstructionMetadata {
  /**
   * \see gd::InstructionMetadata::SetDefaultValue
   */
-  MultipleInstructionMetadata &SetDefaultValue(const gd::String &defaultValue) {
+  MultipleInstructionMetadata &SetDefaultValue(const gd::String &defaultValue) override {
    if (expression) expression->SetDefaultValue(defaultValue);
    if (condition) condition->SetDefaultValue(defaultValue);
    if (action) action->SetDefaultValue(defaultValue);
@@ -85,7 +85,7 @@ class GD_CORE_API MultipleInstructionMetadata {
   * \see gd::InstructionMetadata::SetParameterExtraInfo
   */
  MultipleInstructionMetadata &SetParameterExtraInfo(
-      const gd::String &defaultValue) {
+      const gd::String &defaultValue) override {
    if (expression) expression->SetParameterExtraInfo(defaultValue);
    if (condition) condition->SetParameterExtraInfo(defaultValue);
    if (action) action->SetParameterExtraInfo(defaultValue);
@@ -96,7 +96,7 @@ class GD_CORE_API MultipleInstructionMetadata {
   * \see gd::InstructionMetadata::SetParameterLongDescription
   */
  MultipleInstructionMetadata &SetParameterLongDescription(
-      const gd::String &longDescription) {
+      const gd::String &longDescription) override {
    if (expression) expression->SetParameterLongDescription(longDescription);
    if (condition) condition->SetParameterLongDescription(longDescription);
    if (action) action->SetParameterLongDescription(longDescription);
@@ -106,7 +106,7 @@ class GD_CORE_API MultipleInstructionMetadata {
  /**
   * \see gd::InstructionMetadata::SetHidden
   */
-  MultipleInstructionMetadata &SetHidden() {
+  MultipleInstructionMetadata &SetHidden() override {
    if (expression) expression->SetHidden();
    if (condition) condition->SetHidden();
    if (action) action->SetHidden();
@@ -136,47 +136,47 @@ class GD_CORE_API MultipleInstructionMetadata {
    return *this;
  }

-  MultipleInstructionMetadata &SetFunctionName(const gd::String &functionName) {
+  MultipleInstructionMetadata &SetFunctionName(const gd::String &functionName) override {
    if (expression) expression->SetFunctionName(functionName);
    if (condition) condition->SetFunctionName(functionName);
-    if (action) action->GetCodeExtraInformation().SetFunctionName(functionName);
+    if (action) action->SetFunctionName(functionName);
    return *this;
  }

  MultipleInstructionMetadata &SetGetter(const gd::String &getter) {
    if (expression) expression->SetFunctionName(getter);
    if (condition) condition->SetFunctionName(getter);
-    if (action) action->GetCodeExtraInformation().SetGetter(getter);
+    if (action) action->SetGetter(getter);
    return *this;
  }

-  MultipleInstructionMetadata &SetIncludeFile(const gd::String &includeFile) {
+  MultipleInstructionMetadata &SetIncludeFile(const gd::String &includeFile) override {
    if (expression)
-      expression->GetCodeExtraInformation().SetIncludeFile(includeFile);
+      expression->SetIncludeFile(includeFile);
    if (condition)
-      condition->GetCodeExtraInformation().SetIncludeFile(includeFile);
-    if (action) action->GetCodeExtraInformation().SetIncludeFile(includeFile);
+      condition->SetIncludeFile(includeFile);
+    if (action) action->SetIncludeFile(includeFile);
    return *this;
  }

-  MultipleInstructionMetadata &AddIncludeFile(const gd::String &includeFile) {
+  MultipleInstructionMetadata &AddIncludeFile(const gd::String &includeFile) override {
    if (expression)
      expression->GetCodeExtraInformation().AddIncludeFile(includeFile);
    if (condition)
-      condition->GetCodeExtraInformation().AddIncludeFile(includeFile);
-    if (action) action->GetCodeExtraInformation().AddIncludeFile(includeFile);
+      condition->AddIncludeFile(includeFile);
+    if (action) action->AddIncludeFile(includeFile);
    return *this;
  }

  /**
   * \brief Get the files that must be included to use the instruction.
   */
-  const std::vector<gd::String> &GetIncludeFiles() const {
+  const std::vector<gd::String> &GetIncludeFiles() const override {
    if (expression)
      return expression->GetCodeExtraInformation().GetIncludeFiles();
    if (condition)
-      return condition->GetCodeExtraInformation().GetIncludeFiles();
-    if (action) return action->GetCodeExtraInformation().GetIncludeFiles();
+      return condition->GetIncludeFiles();
+    if (action) return action->GetIncludeFiles();
    // It can't actually happen.
    throw std::logic_error("no instruction metadata");
  }
@@ -184,7 +184,7 @@ class GD_CORE_API MultipleInstructionMetadata {
  /**
   * \see gd::InstructionMetadata::SetPrivate
   */
-  MultipleInstructionMetadata &SetPrivate() {
+  MultipleInstructionMetadata &SetPrivate() override {
    if (expression) expression->SetPrivate();
    if (condition) condition->SetPrivate();
    if (action) action->SetPrivate();
@@ -218,6 +218,42 @@ class GD_CORE_API MultipleInstructionMetadata {
    return *this;
  }

+  /**
+   * Set that the instruction can be used in layouts or external events.
+   */
+  MultipleInstructionMetadata &SetRelevantForLayoutEventsOnly() override {
+    if (condition) condition->SetRelevantForLayoutEventsOnly();
+    if (action) action->SetRelevantForLayoutEventsOnly();
+    return *this;
+  }
+
+  /**
+   * Set that the instruction can be used in function events.
+   */
+  MultipleInstructionMetadata &SetRelevantForFunctionEventsOnly() override {
+    if (condition) condition->SetRelevantForFunctionEventsOnly();
+    if (action) action->SetRelevantForFunctionEventsOnly();
+    return *this;
+  }
+
+  /**
+   * Set that the instruction can be used in asynchronous function events.
+   */
+  MultipleInstructionMetadata &SetRelevantForAsynchronousFunctionEventsOnly() override {
+    if (condition) condition->SetRelevantForAsynchronousFunctionEventsOnly();
+    if (action) action->SetRelevantForAsynchronousFunctionEventsOnly();
+    return *this;
+  }
+
+  /**
+   * Set that the instruction can be used in custom object events.
+   */
+  MultipleInstructionMetadata &SetRelevantForCustomObjectEventsOnly() override {
+    if (condition) condition->SetRelevantForCustomObjectEventsOnly();
+    if (action) action->SetRelevantForCustomObjectEventsOnly();
+    return *this;
+  }
+
  /**
   * \brief Don't use, only here to fulfill Emscripten bindings requirements.
   */
@@ -242,5 +278,3 @@ class GD_CORE_API MultipleInstructionMetadata {
 };

 }  // namespace gd
-
-#endif  // MULTIPLEINSTRUCTIONSMETADATA_H
--- a/Core/GDCore/Extensions/Metadata/ObjectMetadata.h
+++ b/Core/GDCore/Extensions/Metadata/ObjectMetadata.h
@@ -3,8 +3,10 @@
 * Copyright 2008-2016 Florian Rival (Florian.Rival@gmail.com). All rights
 * reserved. This project is released under the MIT License.
 */
-#ifndef OBJECTMETADATA_H
-#define OBJECTMETADATA_H
+#pragma once
+
+#include "InstructionOrExpressionContainerMetadata.h"
+
 #include <functional>
 #include <map>
 #include <set>
@@ -32,7 +34,7 @@ namespace gd {
 *
 * \ingroup Events
 */
-class GD_CORE_API ObjectMetadata {
+class GD_CORE_API ObjectMetadata : public InstructionOrExpressionContainerMetadata {
 public:
  /**
   * \brief Construct an object metadata, using a "blueprint" object that will
@@ -79,7 +81,7 @@ class GD_CORE_API ObjectMetadata {
                                        const gd::String& sentence_,
                                        const gd::String& group_,
                                        const gd::String& icon_,
-                                        const gd::String& smallicon_);
+                                        const gd::String& smallicon_) override;

  /**
   * \brief Declare a new action as being part of the extension.
@@ -92,7 +94,7 @@ class GD_CORE_API ObjectMetadata {
                                     const gd::String& sentence_,
                                     const gd::String& group_,
                                     const gd::String& icon_,
-                                     const gd::String& smallicon_);
+                                     const gd::String& smallicon_) override;

  /**
   * Declare a new condition as being part of the object.
@@ -103,7 +105,7 @@ class GD_CORE_API ObjectMetadata {
                                              const gd::String& sentence_,
                                              const gd::String& group_,
                                              const gd::String& icon_,
-                                              const gd::String& smallicon_);
+                                              const gd::String& smallicon_) override;

  /**
   * Declare a new action as being part of the object.
@@ -114,7 +116,7 @@ class GD_CORE_API ObjectMetadata {
                                           const gd::String& sentence_,
                                           const gd::String& group_,
                                           const gd::String& icon_,
-                                           const gd::String& smallicon_);
+                                           const gd::String& smallicon_) override;

  /**
   * \brief Declare a new expression as being part of the extension.
@@ -123,7 +125,7 @@ class GD_CORE_API ObjectMetadata {
                                        const gd::String& fullname_,
                                        const gd::String& description_,
                                        const gd::String& group_,
-                                        const gd::String& smallicon_);
+                                        const gd::String& smallicon_) override;
  /**
   * \brief Declare a new string expression as being part of the extension.
   */
@@ -131,7 +133,7 @@ class GD_CORE_API ObjectMetadata {
                                           const gd::String& fullname_,
                                           const gd::String& description_,
                                           const gd::String& group_,
-                                           const gd::String& smallicon_);
+                                           const gd::String& smallicon_) override;

  /**
   * \brief Declare a new expression and condition as being part of the
@@ -146,7 +148,7 @@ class GD_CORE_API ObjectMetadata {
      const gd::String& description,
      const gd::String& sentenceName,
      const gd::String& group,
-      const gd::String& icon);
+      const gd::String& icon) override;

  /**
   * \brief Declare a new expression, condition and action as being part of the
@@ -163,7 +165,7 @@ class GD_CORE_API ObjectMetadata {
      const gd::String& description,
      const gd::String& sentenceName,
      const gd::String& group,
-      const gd::String& icon);
+      const gd::String& icon) override;

  /**
   * \brief Create a new action which is the duplicate of the specified one.
@@ -172,7 +174,7 @@ class GD_CORE_API ObjectMetadata {
   * one.
   */
  gd::InstructionMetadata& AddDuplicatedAction(
-      const gd::String& newActionName, const gd::String& copiedActionName);
+      const gd::String& newActionName, const gd::String& copiedActionName) override;

  /**
   * \brief Create a new condition which is the duplicate of the specified one.
@@ -182,23 +184,23 @@ class GD_CORE_API ObjectMetadata {
   */
  gd::InstructionMetadata& AddDuplicatedCondition(
      const gd::String& newConditionName,
-      const gd::String& copiedConditionName);
+      const gd::String& copiedConditionName) override;

  /**
   * \brief Set the name shown to the user.
   */
-  ObjectMetadata& SetFullName(const gd::String& fullname_);
+  ObjectMetadata& SetFullName(const gd::String& fullname_) override;

  /**
   * \brief Set the description shown to the user.
   */
-  ObjectMetadata& SetDescription(const gd::String& description_);
+  ObjectMetadata& SetDescription(const gd::String& description_) override;

  /**
   * \brief Get the help path of the object, relative to the GDevelop
   * documentation root.
   */
-  const gd::String& GetHelpPath() const { return helpPath; }
+  const gd::String& GetHelpPath() const override { return helpPath; }

  /**
   * \brief Set the help path of the object, relative to the GDevelop
@@ -207,7 +209,7 @@ class GD_CORE_API ObjectMetadata {
   * The object instructions will have this help path set by
   * default, unless you call SetHelpPath on them.
   */
-  ObjectMetadata& SetHelpPath(const gd::String& path) {
+  ObjectMetadata& SetHelpPath(const gd::String& path) override {
    helpPath = path;
    return *this;
  }
@@ -222,38 +224,34 @@ class GD_CORE_API ObjectMetadata {
  }

  /**
-   * \brief The "capabilities" that are offered by the base object that are
-   * *not* supported by this object, and should be hidden in the editor
-   * interface.
+   * \brief The "capabilities" that are offered by through behaviors.
   */
-  const std::set<gd::String>& GetUnsupportedBaseObjectCapabilities() const {
-    return unsupportedBaseObjectCapabilities;
+  const std::set<gd::String>& GetDefaultBehaviors() const {
+    return defaultBehaviorTypes;
  }

  /**
-   * \brief Add a "capability" that is offered by the base object that is *not*
-   * supported by this object, and should be hidden in the editor interface.
+   * \brief Return true if object has a default behavior of the given type.
   */
-  ObjectMetadata& AddUnsupportedBaseObjectCapability(
-      const gd::String& capability) {
-    unsupportedBaseObjectCapabilities.insert(capability);
+  bool HasDefaultBehavior(const gd::String& behaviorType) const {
+    return defaultBehaviorTypes.find(behaviorType) != defaultBehaviorTypes.end();
+  }
+
+  /**
+   * \brief Add a "capability" that is offered by through a behavior.
+   */
+  ObjectMetadata& AddDefaultBehavior(
+      const gd::String& behaviorType) {
+    defaultBehaviorTypes.insert(behaviorType);
    return *this;
  }

-  /**
-   * \brief Check if a "capability" that is offered by the base object is *not*
-   * supported by this object, and should be hidden in the editor interface.
-   */
-  bool IsUnsupportedBaseObjectCapability(const gd::String& capability) const {
-    return unsupportedBaseObjectCapabilities.find(capability) != unsupportedBaseObjectCapabilities.end();
-  }
-
-  const gd::String& GetName() const { return name; }
-  const gd::String& GetFullName() const { return fullname; }
+  const gd::String& GetName() const override { return name; }
+  const gd::String& GetFullName() const override { return fullname; }
  const gd::String& GetCategoryFullName() const { return categoryFullName; }
  const gd::String& GetHelpUrl() const { return helpUrl; }
-  const gd::String& GetDescription() const { return description; }
-  const gd::String& GetIconFilename() const { return iconFilename; }
+  const gd::String& GetDescription() const override { return description; }
+  const gd::String& GetIconFilename() const override { return iconFilename; }

  /**
   * \brief Set the URL pointing to the help page about this object
@@ -267,33 +265,33 @@ class GD_CORE_API ObjectMetadata {
   * \note The requirement may vary depending on the platform: Most of the time,
   * the include file contains the declaration of the object.
   */
-  ObjectMetadata& SetIncludeFile(const gd::String& includeFile);
+  ObjectMetadata& SetIncludeFile(const gd::String& includeFile) override;

  /**
   * \brief Add a file to the already existing include files.
   */
-  ObjectMetadata& AddIncludeFile(const gd::String& includeFile);
+  ObjectMetadata& AddIncludeFile(const gd::String& includeFile) override;

  /**
   * \brief Return a reference to a map containing the names of the actions
   * (as keys) and the metadata associated with (as values).
   */
-  std::map<gd::String, gd::InstructionMetadata>& GetAllActions() { return actionsInfos; };
+  std::map<gd::String, gd::InstructionMetadata>& GetAllActions() override { return actionsInfos; };

  /**
   * \see gd::PlatformExtension::GetAllActions
   */
-  std::map<gd::String, gd::InstructionMetadata>& GetAllConditions() { return conditionsInfos; };
+  std::map<gd::String, gd::InstructionMetadata>& GetAllConditions() override { return conditionsInfos; };

  /**
   * \see gd::PlatformExtension::GetAllActions
   */
-  std::map<gd::String, gd::ExpressionMetadata>& GetAllExpressions() { return expressionsInfos; };
+  std::map<gd::String, gd::ExpressionMetadata>& GetAllExpressions() override { return expressionsInfos; };

  /**
   * \see gd::PlatformExtension::GetAllActions
   */
-  std::map<gd::String, gd::ExpressionMetadata>& GetAllStrExpressions() { return strExpressionsInfos; };
+  std::map<gd::String, gd::ExpressionMetadata>& GetAllStrExpressions() override { return strExpressionsInfos; };

  /**
   * \brief Set the object to be hidden in the IDE.
@@ -329,7 +327,7 @@ class GD_CORE_API ObjectMetadata {
  gd::String description;
  gd::String iconFilename;
  gd::String categoryFullName;
-  std::set<gd::String> unsupportedBaseObjectCapabilities;
+  std::set<gd::String> defaultBehaviorTypes;
  bool hidden = false;

  std::shared_ptr<gd::ObjectConfiguration>
@@ -341,4 +339,3 @@ class GD_CORE_API ObjectMetadata {
 };

 }  // namespace gd
-#endif  // OBJECTMETADATA_H
--- a/Core/GDCore/Extensions/PlatformExtension.cpp
+++ b/Core/GDCore/Extensions/PlatformExtension.cpp
@@ -273,25 +273,6 @@ gd::BehaviorMetadata& PlatformExtension::AddBehavior(
  return behaviorsInfo[nameWithNamespace];
 }

-gd::BehaviorMetadata& PlatformExtension::AddEventsBasedBehavior(
-    const gd::String& name,
-    const gd::String& fullname,
-    const gd::String& description,
-    const gd::String& group,
-    const gd::String& icon24x24) {
-  gd::String nameWithNamespace = GetNameSpace() + name;
-  behaviorsInfo[nameWithNamespace] = BehaviorMetadata(GetNameSpace(),
-                                                      nameWithNamespace,
-                                                      fullname,
-                                                      // Default name is the name
-                                                      name,
-                                                      description,
-                                                      group,
-                                                      icon24x24)
-                                         .SetHelpPath(GetHelpPath());
-  return behaviorsInfo[nameWithNamespace];
-}
-
 gd::EffectMetadata& PlatformExtension::AddEffect(const gd::String& name) {
  gd::String nameWithNamespace = GetNameSpace() + name;
  effectsMetadata[nameWithNamespace] = EffectMetadata(nameWithNamespace);
@@ -653,7 +634,7 @@ void PlatformExtension::StripUnimplementedInstructionsAndExpressions() {
           GetAllActions().begin();
       it != GetAllActions().end();) {
    if (it->second.codeExtraInformation.functionCallName.empty() &&
-        !it->second.codeExtraInformation.HasCustomCodeGenerator()) {
+        !it->second.HasCustomCodeGenerator()) {
      GetAllActions().erase(it++);
    } else
      ++it;
@@ -663,7 +644,7 @@ void PlatformExtension::StripUnimplementedInstructionsAndExpressions() {
           GetAllConditions().begin();
       it != GetAllConditions().end();) {
    if (it->second.codeExtraInformation.functionCallName.empty() &&
-        !it->second.codeExtraInformation.HasCustomCodeGenerator()) {
+        !it->second.HasCustomCodeGenerator()) {
      GetAllConditions().erase(it++);
    } else
      ++it;
@@ -673,7 +654,7 @@ void PlatformExtension::StripUnimplementedInstructionsAndExpressions() {
           GetAllExpressions().begin();
       it != GetAllExpressions().end();) {
    if (it->second.codeExtraInformation.functionCallName.empty() &&
-        !it->second.codeExtraInformation.HasCustomCodeGenerator()) {
+        !it->second.HasCustomCodeGenerator()) {
      GetAllExpressions().erase(it++);
    } else
      ++it;
@@ -683,7 +664,7 @@ void PlatformExtension::StripUnimplementedInstructionsAndExpressions() {
           GetAllStrExpressions().begin();
       it != GetAllStrExpressions().end();) {
    if (it->second.codeExtraInformation.functionCallName.empty() &&
-        !it->second.codeExtraInformation.HasCustomCodeGenerator()) {
+        !it->second.HasCustomCodeGenerator()) {
      GetAllStrExpressions().erase(it++);
    } else
      ++it;
@@ -699,7 +680,7 @@ void PlatformExtension::StripUnimplementedInstructionsAndExpressions() {
             obj.actionsInfos.begin();
         it != obj.actionsInfos.end();) {
      if (it->second.codeExtraInformation.functionCallName.empty() &&
-          !it->second.codeExtraInformation.HasCustomCodeGenerator()) {
+          !it->second.HasCustomCodeGenerator()) {
        obj.actionsInfos.erase(it++);
      } else
        ++it;
@@ -709,7 +690,7 @@ void PlatformExtension::StripUnimplementedInstructionsAndExpressions() {
             obj.conditionsInfos.begin();
         it != obj.conditionsInfos.end();) {
      if (it->second.codeExtraInformation.functionCallName.empty() &&
-          !it->second.codeExtraInformation.HasCustomCodeGenerator()) {
+          !it->second.HasCustomCodeGenerator()) {
        obj.conditionsInfos.erase(it++);
      } else
        ++it;
@@ -719,7 +700,7 @@ void PlatformExtension::StripUnimplementedInstructionsAndExpressions() {
             obj.expressionsInfos.begin();
         it != obj.expressionsInfos.end();) {
      if (it->second.codeExtraInformation.functionCallName.empty() &&
-          !it->second.codeExtraInformation.HasCustomCodeGenerator()) {
+          !it->second.HasCustomCodeGenerator()) {
        obj.expressionsInfos.erase(it++);
      } else
        ++it;
@@ -729,7 +710,7 @@ void PlatformExtension::StripUnimplementedInstructionsAndExpressions() {
             obj.strExpressionsInfos.begin();
         it != obj.strExpressionsInfos.end();) {
      if (it->second.codeExtraInformation.functionCallName.empty() &&
-          !it->second.codeExtraInformation.HasCustomCodeGenerator()) {
+          !it->second.HasCustomCodeGenerator()) {
        obj.strExpressionsInfos.erase(it++);
      } else
        ++it;
@@ -746,7 +727,7 @@ void PlatformExtension::StripUnimplementedInstructionsAndExpressions() {
             obj.actionsInfos.begin();
         it != obj.actionsInfos.end();) {
      if (it->second.codeExtraInformation.functionCallName.empty() &&
-          !it->second.codeExtraInformation.HasCustomCodeGenerator()) {
+          !it->second.HasCustomCodeGenerator()) {
        obj.actionsInfos.erase(it++);
      } else
        ++it;
@@ -756,7 +737,7 @@ void PlatformExtension::StripUnimplementedInstructionsAndExpressions() {
             obj.conditionsInfos.begin();
         it != obj.conditionsInfos.end();) {
      if (it->second.codeExtraInformation.functionCallName.empty() &&
-          !it->second.codeExtraInformation.HasCustomCodeGenerator()) {
+          !it->second.HasCustomCodeGenerator()) {
        obj.conditionsInfos.erase(it++);
      } else
        ++it;
@@ -766,7 +747,7 @@ void PlatformExtension::StripUnimplementedInstructionsAndExpressions() {
             obj.expressionsInfos.begin();
         it != obj.expressionsInfos.end();) {
      if (it->second.codeExtraInformation.functionCallName.empty() &&
-          !it->second.codeExtraInformation.HasCustomCodeGenerator()) {
+          !it->second.HasCustomCodeGenerator()) {
        obj.expressionsInfos.erase(it++);
      } else
        ++it;
@@ -776,7 +757,7 @@ void PlatformExtension::StripUnimplementedInstructionsAndExpressions() {
             obj.strExpressionsInfos.begin();
         it != obj.strExpressionsInfos.end();) {
      if (it->second.codeExtraInformation.functionCallName.empty() &&
-          !it->second.codeExtraInformation.HasCustomCodeGenerator()) {
+          !it->second.HasCustomCodeGenerator()) {
        obj.strExpressionsInfos.erase(it++);
      } else
        ++it;
--- a/Core/GDCore/Extensions/PlatformExtension.h
+++ b/Core/GDCore/Extensions/PlatformExtension.h
@@ -421,6 +421,32 @@ class GD_CORE_API PlatformExtension {
   */
  const gd::String& GetIconUrl() const { return iconUrl; }

+  /**
+   * \brief Return keywords that help search engines find this extension.
+   */
+  const std::vector<gd::String>& GetTags() const { return tags; }
+
+  /**
+   * \brief Set keywords that help search engines find this extension.
+   */
+  PlatformExtension& SetTags(const gd::String& csvTags) {
+    tags.clear();
+    tags = csvTags.Split(',');
+    for (size_t i = 0; i < tags.size(); i++)
+    {
+      tags[i] = tags[i].Trim().LowerCase();
+    }
+    return *this;
+  }
+
+  /**
+   * \brief Add a keyword that help search engines find this extension.
+   */
+  PlatformExtension& AddTag(const gd::String& tag) {
+    tags.push_back(tag);
+    return *this;
+  }
+
  /**
   * \brief Check if the extension is flagged as being deprecated.
   */
@@ -661,6 +687,7 @@ private:
  gd::String helpPath;  ///< The relative path to the help for this extension in
                        ///< the documentation.
  gd::String iconUrl;   ///< The URL to the icon to be shown for this extension.
+  std::vector<gd::String> tags;

  std::map<gd::String, gd::ObjectMetadata> objectsInfos;
  std::map<gd::String, gd::BehaviorMetadata> behaviorsInfo;
--- a/Core/GDCore/IDE/Events/BehaviorDefaultFlagClearer.cpp
+++ b/Core/GDCore/IDE/Events/BehaviorDefaultFlagClearer.cpp
@@ -0,0 +1,23 @@
+#include "BehaviorDefaultFlagClearer.h"
+
+#include "GDCore/Events/Instruction.h"
+#include "GDCore/Extensions/Metadata/MetadataProvider.h"
+#include "GDCore/Extensions/PlatformExtension.h"
+#include "GDCore/IDE/WholeProjectRefactorer.h"
+#include "GDCore/IDE/Events/ExpressionTypeFinder.h"
+#include "GDCore/Project/Behavior.h"
+#include "GDCore/Project/Object.h"
+#include "GDCore/Project/Project.h"
+
+namespace gd {
+
+void BehaviorDefaultFlagClearer::DoVisitObject(gd::Object& object) {
+};
+
+void BehaviorDefaultFlagClearer::DoVisitBehavior(gd::Behavior& behavior) {
+  behavior.SetDefaultBehavior(false);
+};
+
+BehaviorDefaultFlagClearer::~BehaviorDefaultFlagClearer() {}
+
+}  // namespace gd
--- a/Core/GDCore/IDE/Events/BehaviorDefaultFlagClearer.h
+++ b/Core/GDCore/IDE/Events/BehaviorDefaultFlagClearer.h
@@ -0,0 +1,34 @@
+/*
+ * GDevelop Core
+ * Copyright 2008-2016 Florian Rival (Florian.Rival@gmail.com). All rights
+ * reserved. This project is released under the MIT License.
+ */
+
+#pragma once
+#include <set>
+
+#include "GDCore/IDE/Project/ArbitraryObjectsWorker.h"
+#include "GDCore/String.h"
+
+namespace gd {
+class Object;
+class Behavior;
+}  // namespace gd
+
+namespace gd {
+
+/**
+ * @brief This is used for project exports to keep default behaviors in
+ * serialized data used by Runtime.
+ */
+class GD_CORE_API BehaviorDefaultFlagClearer : public ArbitraryObjectsWorker {
+ public:
+  BehaviorDefaultFlagClearer() {};
+  virtual ~BehaviorDefaultFlagClearer();
+
+ private:
+  void DoVisitObject(gd::Object& object) override;
+  void DoVisitBehavior(gd::Behavior& behavior) override;
+};
+
+};  // namespace gd
--- a/Core/GDCore/IDE/Events/EventsRefactorer.cpp
+++ b/Core/GDCore/IDE/Events/EventsRefactorer.cpp
@@ -555,6 +555,22 @@ void EventsRefactorer::RemoveObjectInEvents(const gd::Platform& platform,
  }
 }

+gd::String ReplaceAllOccurrencesCaseInsensitive(gd::String context,
+                                                const gd::String& from,
+                                                const gd::String& to) {
+  size_t lookHere = 0;
+  size_t foundHere;
+  size_t fromSize = from.size();
+  size_t toSize = to.size();
+  while ((foundHere = context.FindCaseInsensitive(from, lookHere)) !=
+         gd::String::npos) {
+    context.replace(foundHere, fromSize, to);
+    lookHere = foundHere + toSize;
+  }
+
+  return context;
+}
+
 std::vector<EventsSearchResult> EventsRefactorer::ReplaceStringInEvents(
    gd::ObjectsContainer& project,
    gd::ObjectsContainer& layout,
@@ -570,6 +586,32 @@ std::vector<EventsSearchResult> EventsRefactorer::ReplaceStringInEvents(

  for (std::size_t i = 0; i < events.size(); ++i) {
    bool eventModified = false;
+
+    std::vector<gd::Expression*> allObjectExpressions =
+        events[i].GetAllObjectExpressions();
+    for (std::size_t j = 0; j < allObjectExpressions.size(); ++j) {
+      gd::String newExpressionPlainString =
+          matchCase ? allObjectExpressions[j]->GetPlainString().FindAndReplace(
+                          toReplace, newString, true)
+                    : ReplaceAllOccurrencesCaseInsensitive(
+                          allObjectExpressions[j]->GetPlainString(),
+                          toReplace,
+                          newString);
+
+      if (newExpressionPlainString !=
+          allObjectExpressions[j]->GetPlainString()) {
+        *allObjectExpressions[j] = gd::Expression(newExpressionPlainString);
+
+        if (!eventModified) {
+          modifiedEvents.push_back(EventsSearchResult(
+              std::weak_ptr<gd::BaseEvent>(events.GetEventSmartPtr(i)),
+              &events,
+              i));
+          eventModified = true;
+        }
+      }
+    }
+
    if (inConditions) {
      vector<gd::InstructionsList*> conditionsVectors =
          events[i].GetAllConditionsVectors();
@@ -642,22 +684,6 @@ std::vector<EventsSearchResult> EventsRefactorer::ReplaceStringInEvents(
  return modifiedEvents;
 }

-gd::String ReplaceAllOccurencesCaseUnsensitive(gd::String context,
-                                               gd::String from,
-                                               const gd::String& to) {
-  size_t lookHere = 0;
-  size_t foundHere;
-  size_t fromSize = from.size();
-  size_t toSize = to.size();
-  while ((foundHere = context.FindCaseInsensitive(from, lookHere)) !=
-         gd::String::npos) {
-    context.replace(foundHere, fromSize, to);
-    lookHere = foundHere + toSize;
-  }
-
-  return context;
-}
-
 bool EventsRefactorer::ReplaceStringInActions(gd::ObjectsContainer& project,
                                              gd::ObjectsContainer& layout,
                                              gd::InstructionsList& actions,
@@ -673,7 +699,7 @@ bool EventsRefactorer::ReplaceStringInActions(gd::ObjectsContainer& project,
          matchCase
              ? actions[aId].GetParameter(pNb).GetPlainString().FindAndReplace(
                    toReplace, newString, true)
-              : ReplaceAllOccurencesCaseUnsensitive(
+              : ReplaceAllOccurrencesCaseInsensitive(
                    actions[aId].GetParameter(pNb).GetPlainString(),
                    toReplace,
                    newString);
@@ -713,7 +739,7 @@ bool EventsRefactorer::ReplaceStringInConditions(
                          .GetParameter(pNb)
                          .GetPlainString()
                          .FindAndReplace(toReplace, newString, true)
-                    : ReplaceAllOccurencesCaseUnsensitive(
+                    : ReplaceAllOccurrencesCaseInsensitive(
                          conditions[cId].GetParameter(pNb).GetPlainString(),
                          toReplace,
                          newString);
@@ -749,7 +775,7 @@ bool EventsRefactorer::ReplaceStringInEventSearchableStrings(
  for (std::size_t sNb = 0; sNb < stringEvent.size(); ++sNb) {
    gd::String newStringEvent =
        matchCase ? stringEvent[sNb].FindAndReplace(toReplace, newString, true)
-                  : ReplaceAllOccurencesCaseUnsensitive(
+                  : ReplaceAllOccurrencesCaseInsensitive(
                        stringEvent[sNb], toReplace, newString);
    newEventStrings.push_back(newStringEvent);
  }
@@ -789,6 +815,24 @@ vector<EventsSearchResult> EventsRefactorer::SearchInEvents(
  for (std::size_t i = 0; i < events.size(); ++i) {
    bool eventAddedInResults = false;

+    std::vector<gd::Expression*> allObjectExpressions =
+        events[i].GetAllObjectExpressions();
+    for (std::size_t j = 0; j < allObjectExpressions.size(); ++j) {
+      size_t foundPosition =
+          matchCase
+              ? allObjectExpressions[j]->GetPlainString().find(search)
+              : allObjectExpressions[j]->GetPlainString().FindCaseInsensitive(
+                    search);
+
+      if (foundPosition != gd::String::npos && !eventAddedInResults) {
+        results.push_back(EventsSearchResult(
+            std::weak_ptr<gd::BaseEvent>(events.GetEventSmartPtr(i)),
+            &events,
+            i));
+        eventAddedInResults = true;
+      }
+    }
+
    if (inConditions) {
      vector<gd::InstructionsList*> conditionsVectors =
          events[i].GetAllConditionsVectors();
@@ -803,6 +847,7 @@ vector<EventsSearchResult> EventsRefactorer::SearchInEvents(
              std::weak_ptr<gd::BaseEvent>(events.GetEventSmartPtr(i)),
              &events,
              i));
+          eventAddedInResults = true;
        }
      }
    }
@@ -820,6 +865,7 @@ vector<EventsSearchResult> EventsRefactorer::SearchInEvents(
              std::weak_ptr<gd::BaseEvent>(events.GetEventSmartPtr(i)),
              &events,
              i));
+          eventAddedInResults = true;
        }
      }
    }
--- a/Core/GDCore/IDE/Events/ExpressionValidator.cpp
+++ b/Core/GDCore/IDE/Events/ExpressionValidator.cpp
@@ -104,14 +104,6 @@ ExpressionValidator::Type ExpressionValidator::ValidateFunction(const gd::Functi
  !metadata.GetRequiredBaseObjectCapability().empty()) {
    const gd::ObjectMetadata &objectMetadata =
        MetadataProvider::GetObjectMetadata(platform, objectType);
-
-    if (objectMetadata.IsUnsupportedBaseObjectCapability(
-            metadata.GetRequiredBaseObjectCapability())) {
-      RaiseTypeError(
-          _("This expression exists, but it can't be used on this object."),
-          function.objectNameLocation);
-      return returnType;
-    }
  }

  if (gd::MetadataProvider::IsBadExpressionMetadata(metadata)) {
--- a/Core/GDCore/IDE/Events/ProjectElementRenamer.cpp
+++ b/Core/GDCore/IDE/Events/ProjectElementRenamer.cpp
@@ -87,11 +87,22 @@ protected:
            std::unique_ptr<gd::ExpressionNode> &parameterNode,
            size_t parameterIndex, const gd::String &lastObjectName) {
          if (parameterMetadata.GetType() == "layer") {
-            // Remove quotes, it won't match if it's not a literal anyway.
-            lastLayerName = expressionPlainString.substr(
-                parameterNode->location.GetStartPosition() + 1,
-                parameterNode->location.GetEndPosition() -
-                    parameterNode->location.GetStartPosition() - 2);
+            if (parameterNode->location.GetEndPosition() -
+                    parameterNode->location.GetStartPosition() <
+                2) {
+              // This is either the base layer or an invalid layer name.
+              // Keep it as is.
+              lastLayerName = expressionPlainString.substr(
+                  parameterNode->location.GetStartPosition(),
+                  parameterNode->location.GetEndPosition() -
+                      parameterNode->location.GetStartPosition());
+            } else {
+              // Remove quotes, so it can be compared to the layer name.
+              lastLayerName = expressionPlainString.substr(
+                  parameterNode->location.GetStartPosition() + 1,
+                  parameterNode->location.GetEndPosition() -
+                      parameterNode->location.GetStartPosition() - 2);
+            }
          }
          if (parameterMetadata.GetType() == parameterType) {
            auto parameterExpressionPlainString = expressionPlainString.substr(
@@ -143,9 +154,15 @@ bool ProjectElementRenamer::DoVisitInstruction(gd::Instruction &instruction,
          const gd::Expression &parameterValue, size_t parameterIndex,
          const gd::String &lastObjectName) {
        if (parameterMetadata.GetType() == "layer") {
-          // Remove quotes, it won't match if it's not a literal anyway.
-          lastLayerName = parameterValue.GetPlainString().substr(
-              1, parameterValue.GetPlainString().length() - 2);
+          if (parameterValue.GetPlainString().length() < 2) {
+            // This is either the base layer or an invalid layer name.
+            // Keep it as is.
+            lastLayerName = parameterValue.GetPlainString();
+          } else {
+            // Remove quotes, so it can be compared to the layer name.
+            lastLayerName = parameterValue.GetPlainString().substr(
+                1, parameterValue.GetPlainString().length() - 2);
+          }
        }

        if (parameterMetadata.GetType() == parameterType &&
@@ -165,7 +182,6 @@ bool ProjectElementRenamer::DoVisitInstruction(gd::Instruction &instruction,
          node->Visit(finder);

          if (finder.GetOccurrences().size() > 0) {
-
            gd::String newNameWithQuotes = "\"" + newName + "\"";
            gd::String oldParameterValue = parameterValue.GetPlainString();
            gd::String newParameterValue;
--- a/Core/GDCore/IDE/Project/ArbitraryResourceWorker.cpp
+++ b/Core/GDCore/IDE/Project/ArbitraryResourceWorker.cpp
@@ -17,9 +17,11 @@
 #include "GDCore/Extensions/Metadata/ParameterMetadataTools.h"
 #include "GDCore/Extensions/Platform.h"
 #include "GDCore/Extensions/PlatformExtension.h"
-#include "GDCore/IDE/Events/ArbitraryEventsWorker.h"
 #include "GDCore/Project/Project.h"
 #include "GDCore/Project/ResourcesManager.h"
+#include "GDCore/Project/Effect.h"
+#include "GDCore/Tools/Log.h"
+#include "GDCore/IDE/ResourceExposer.h"

 using namespace std;

@@ -131,29 +133,9 @@ void ArbitraryResourceWorker::ExposeEmbeddeds(gd::String& resourceName) {
          std::cout << targetResourceName << std::endl;
          gd::Resource& targetResource =
              resourcesManager->GetResource(targetResourceName);
-          const gd::String& targetResourceKind = targetResource.GetKind();

          gd::String potentiallyUpdatedTargetResourceName = targetResourceName;
-
-          if (targetResourceKind == "audio") {
-            ExposeAudio(potentiallyUpdatedTargetResourceName);
-          } else if (targetResourceKind == "bitmapFont") {
-            ExposeBitmapFont(potentiallyUpdatedTargetResourceName);
-          } else if (targetResourceKind == "font") {
-            ExposeFont(potentiallyUpdatedTargetResourceName);
-          } else if (targetResourceKind == "image") {
-            ExposeImage(potentiallyUpdatedTargetResourceName);
-          } else if (targetResourceKind == "json") {
-            ExposeJson(potentiallyUpdatedTargetResourceName);
-          } else if (targetResourceKind == "tilemap") {
-            ExposeTilemap(potentiallyUpdatedTargetResourceName);
-          } else if (targetResourceKind == "tileset") {
-            ExposeTileset(potentiallyUpdatedTargetResourceName);
-          } else if (targetResourceKind == "video") {
-            ExposeVideo(potentiallyUpdatedTargetResourceName);
-          } else if (targetResourceKind == "model3D") {
-            ExposeModel3D(potentiallyUpdatedTargetResourceName);
-          }
+          ExposeResourceWithType(targetResource.GetKind(), potentiallyUpdatedTargetResourceName);

          if (potentiallyUpdatedTargetResourceName != targetResourceName) {
            // The resource name was renamed. Also update the mapping.
@@ -170,6 +152,48 @@ void ArbitraryResourceWorker::ExposeEmbeddeds(gd::String& resourceName) {
  }
 }

+void ArbitraryResourceWorker::ExposeResourceWithType(
+    const gd::String &resourceType, gd::String &resourceName) {
+  if (resourceType == "image") {
+    ExposeImage(resourceName);
+    return;
+  }
+  if (resourceType == "model3D") {
+    ExposeModel3D(resourceName);
+    return;
+  }
+  if (resourceType == "audio") {
+    ExposeAudio(resourceName);
+    return;
+  }
+  if (resourceType == "font") {
+    ExposeFont(resourceName);
+    return;
+  }
+  if (resourceType == "bitmapFont") {
+    ExposeBitmapFont(resourceName);
+    return;
+  }
+  if (resourceType == "tilemap") {
+    ExposeTilemap(resourceName);
+    return;
+  }
+  if (resourceType == "tileset") {
+    ExposeTileset(resourceName);
+    return;
+  }
+  if (resourceType == "json") {
+    ExposeJson(resourceName);
+    return;
+  }
+  if (resourceType == "video") {
+    ExposeVideo(resourceName);
+    return;
+  }
+  gd::LogError("Unexpected resource type: " + resourceType + " for: " + resourceName);
+  return;
+}
+
 void ArbitraryResourceWorker::ExposeResource(gd::Resource& resource) {
  if (!resource.UseFile()) return;

@@ -180,86 +204,98 @@ void ArbitraryResourceWorker::ExposeResource(gd::Resource& resource) {

 ArbitraryResourceWorker::~ArbitraryResourceWorker() {}

-/**
- * Launch the specified resource worker on every resource referenced in the
- * events.
- */
-class ResourceWorkerInEventsWorker : public ArbitraryEventsWorker {
- public:
-  ResourceWorkerInEventsWorker(const gd::Project& project_,
-                               gd::ArbitraryResourceWorker& worker_)
-      : project(project_), worker(worker_){};
-  virtual ~ResourceWorkerInEventsWorker(){};
+bool ResourceWorkerInEventsWorker::DoVisitInstruction(gd::Instruction& instruction, bool isCondition) {
+  const auto& platform = project.GetCurrentPlatform();
+  const auto& metadata = isCondition
+                              ? gd::MetadataProvider::GetConditionMetadata(
+                                    platform, instruction.GetType())
+                              : gd::MetadataProvider::GetActionMetadata(
+                                    platform, instruction.GetType());

- private:
-  bool DoVisitInstruction(gd::Instruction& instruction, bool isCondition) {
-    const auto& platform = project.GetCurrentPlatform();
-    const auto& metadata = isCondition
-                               ? gd::MetadataProvider::GetConditionMetadata(
-                                     platform, instruction.GetType())
-                               : gd::MetadataProvider::GetActionMetadata(
-                                     platform, instruction.GetType());
+  gd::ParameterMetadataTools::IterateOverParametersWithIndex(
+      instruction.GetParameters(),
+      metadata.GetParameters(),
+      [this, &instruction](const gd::ParameterMetadata& parameterMetadata,
+                            const gd::Expression& parameterExpression,
+                            size_t parameterIndex,
+                            const gd::String& lastObjectName) {
+        const String& parameterValue = parameterExpression.GetPlainString();
+        if (parameterMetadata.GetType() ==
+                "police" ||  // Should be renamed fontResource
+            parameterMetadata.GetType() == "fontResource") {
+          gd::String updatedParameterValue = parameterValue;
+          worker.ExposeFont(updatedParameterValue);
+          instruction.SetParameter(parameterIndex, updatedParameterValue);
+        } else if (parameterMetadata.GetType() == "soundfile" ||
+                    parameterMetadata.GetType() ==
+                        "musicfile") {  // Should be renamed audioResource
+          gd::String updatedParameterValue = parameterValue;
+          worker.ExposeAudio(updatedParameterValue);
+          instruction.SetParameter(parameterIndex, updatedParameterValue);
+        } else if (parameterMetadata.GetType() == "bitmapFontResource") {
+          gd::String updatedParameterValue = parameterValue;
+          worker.ExposeBitmapFont(updatedParameterValue);
+          instruction.SetParameter(parameterIndex, updatedParameterValue);
+        } else if (parameterMetadata.GetType() == "imageResource") {
+          gd::String updatedParameterValue = parameterValue;
+          worker.ExposeImage(updatedParameterValue);
+          instruction.SetParameter(parameterIndex, updatedParameterValue);
+        } else if (parameterMetadata.GetType() == "jsonResource") {
+          gd::String updatedParameterValue = parameterValue;
+          worker.ExposeJson(updatedParameterValue);
+          instruction.SetParameter(parameterIndex, updatedParameterValue);
+        } else if (parameterMetadata.GetType() == "tilemapResource") {
+          gd::String updatedParameterValue = parameterValue;
+          worker.ExposeTilemap(updatedParameterValue);
+          instruction.SetParameter(parameterIndex, updatedParameterValue);
+        } else if (parameterMetadata.GetType() == "tilesetResource") {
+          gd::String updatedParameterValue = parameterValue;
+          worker.ExposeTileset(updatedParameterValue);
+          instruction.SetParameter(parameterIndex, updatedParameterValue);
+        } else if (parameterMetadata.GetType() == "model3DResource") {
+          gd::String updatedParameterValue = parameterValue;
+          worker.ExposeModel3D(updatedParameterValue);
+          instruction.SetParameter(parameterIndex, updatedParameterValue);
+        }
+      });

-    gd::ParameterMetadataTools::IterateOverParametersWithIndex(
-        instruction.GetParameters(),
-        metadata.GetParameters(),
-        [this, &instruction](const gd::ParameterMetadata& parameterMetadata,
-                             const gd::Expression& parameterExpression,
-                             size_t parameterIndex,
-                             const gd::String& lastObjectName) {
-          const String& parameterValue = parameterExpression.GetPlainString();
-          if (parameterMetadata.GetType() ==
-                  "police" ||  // Should be renamed fontResource
-              parameterMetadata.GetType() == "fontResource") {
-            gd::String updatedParameterValue = parameterValue;
-            worker.ExposeFont(updatedParameterValue);
-            instruction.SetParameter(parameterIndex, updatedParameterValue);
-          } else if (parameterMetadata.GetType() == "soundfile" ||
-                     parameterMetadata.GetType() ==
-                         "musicfile") {  // Should be renamed audioResource
-            gd::String updatedParameterValue = parameterValue;
-            worker.ExposeAudio(updatedParameterValue);
-            instruction.SetParameter(parameterIndex, updatedParameterValue);
-          } else if (parameterMetadata.GetType() == "bitmapFontResource") {
-            gd::String updatedParameterValue = parameterValue;
-            worker.ExposeBitmapFont(updatedParameterValue);
-            instruction.SetParameter(parameterIndex, updatedParameterValue);
-          } else if (parameterMetadata.GetType() == "imageResource") {
-            gd::String updatedParameterValue = parameterValue;
-            worker.ExposeImage(updatedParameterValue);
-            instruction.SetParameter(parameterIndex, updatedParameterValue);
-          } else if (parameterMetadata.GetType() == "jsonResource") {
-            gd::String updatedParameterValue = parameterValue;
-            worker.ExposeJson(updatedParameterValue);
-            instruction.SetParameter(parameterIndex, updatedParameterValue);
-          } else if (parameterMetadata.GetType() == "tilemapResource") {
-            gd::String updatedParameterValue = parameterValue;
-            worker.ExposeTilemap(updatedParameterValue);
-            instruction.SetParameter(parameterIndex, updatedParameterValue);
-          } else if (parameterMetadata.GetType() == "tilesetResource") {
-            gd::String updatedParameterValue = parameterValue;
-            worker.ExposeTileset(updatedParameterValue);
-            instruction.SetParameter(parameterIndex, updatedParameterValue);
-          } else if (parameterMetadata.GetType() == "model3DResource") {
-            gd::String updatedParameterValue = parameterValue;
-            worker.ExposeModel3D(updatedParameterValue);
-            instruction.SetParameter(parameterIndex, updatedParameterValue);
-          }
-        });
-
-    return false;
-  };
-
-  const gd::Project& project;
-  gd::ArbitraryResourceWorker& worker;
+  return false;
 };

 void LaunchResourceWorkerOnEvents(const gd::Project& project,
                                  gd::EventsList& events,
                                  gd::ArbitraryResourceWorker& worker) {
-  ResourceWorkerInEventsWorker eventsWorker(project, worker);
+  gd::ResourceWorkerInEventsWorker eventsWorker(project, worker);
  eventsWorker.Launch(events);
 }

+gd::ResourceWorkerInEventsWorker
+GetResourceWorkerOnEvents(const gd::Project &project,
+                          gd::ArbitraryResourceWorker &worker) {
+  gd::ResourceWorkerInEventsWorker eventsWorker(project, worker);
+  return eventsWorker;
+}
+
+void ResourceWorkerInObjectsWorker::DoVisitObject(gd::Object &object) {
+  object.GetConfiguration().ExposeResources(worker);
+  auto& effects = object.GetEffects();
+  for (size_t effectIndex = 0; effectIndex < effects.GetEffectsCount(); effectIndex++)
+  {
+    auto& effect = effects.GetEffect(effectIndex);
+    gd::ResourceExposer::ExposeEffectResources(project.GetCurrentPlatform(), effect, worker);
+  }
+};
+
+void ResourceWorkerInObjectsWorker::DoVisitBehavior(gd::Behavior &behavior){
+    // TODO Allow behaviors to expose resources
+};
+
+gd::ResourceWorkerInObjectsWorker
+GetResourceWorkerOnObjects(const gd::Project &project,
+                           gd::ArbitraryResourceWorker &worker) {
+  gd::ResourceWorkerInObjectsWorker eventsWorker(project, worker);
+  return eventsWorker;
+}
+
 }  // namespace gd
 #endif
--- a/Core/GDCore/IDE/Project/ArbitraryResourceWorker.h
+++ b/Core/GDCore/IDE/Project/ArbitraryResourceWorker.h
@@ -4,13 +4,14 @@
 * reserved. This project is released under the MIT License.
 */

-#ifndef ARBITRARYRESOURCEWORKER_H
-#define ARBITRARYRESOURCEWORKER_H
+#pragma once

 #include <map>
 #include <memory>
 #include <vector>
 #include "GDCore/String.h"
+#include "GDCore/IDE/Events/ArbitraryEventsWorker.h"
+#include "GDCore/IDE/Project/ArbitraryObjectsWorker.h"
 namespace gd {
 class BaseEvent;
 }
@@ -53,6 +54,11 @@ class GD_CORE_API ArbitraryResourceWorker {
   */
  void ExposeResources(gd::ResourcesManager *resourcesManager);

+  /**
+   * \brief Expose a resource from a given type.
+   */
+  void ExposeResourceWithType(const gd::String& resourceType, gd::String& resourceName);
+
  /**
   * \brief Expose an image, which is always a reference to a "image" resource.
   */
@@ -132,18 +138,47 @@ class GD_CORE_API ArbitraryResourceWorker {
 };

 /**
- * Tool function iterating over each event and calling
- * Expose(Actions/Conditions)Resources for each actions and conditions with the
- * ArbitraryResourceWorker passed as argument.
- *
- * \see gd::ArbitraryResourceWorker
- * \ingroup IDE
+ * Launch the specified resource worker on every resource referenced in the
+ * events.
 */
-void GD_CORE_API
-LaunchResourceWorkerOnEvents(const gd::Project &project,
-                             gd::EventsList &events,
-                             gd::ArbitraryResourceWorker &worker);
+class ResourceWorkerInEventsWorker : public gd::ArbitraryEventsWorker {
+public:
+  ResourceWorkerInEventsWorker(const gd::Project &project_,
+                               gd::ArbitraryResourceWorker &worker_)
+      : project(project_), worker(worker_){};
+  virtual ~ResourceWorkerInEventsWorker(){};
+
+private:
+  bool DoVisitInstruction(gd::Instruction &instruction,
+                          bool isCondition) override;
+
+  const gd::Project &project;
+  gd::ArbitraryResourceWorker &worker;
+};
+
+ResourceWorkerInEventsWorker GD_CORE_API GetResourceWorkerOnEvents(
+    const gd::Project &project, gd::ArbitraryResourceWorker &worker);
+
+/**
+ * Launch the specified resource worker on every resource referenced in the
+ * objects.
+ */
+class GD_CORE_API ResourceWorkerInObjectsWorker
+    : public gd::ArbitraryObjectsWorker {
+public:
+  ResourceWorkerInObjectsWorker(const gd::Project &project_, gd::ArbitraryResourceWorker &worker_)
+      : project(project_), worker(worker_){};
+  ~ResourceWorkerInObjectsWorker() {}
+
+private:
+  void DoVisitObject(gd::Object &object) override;
+  void DoVisitBehavior(gd::Behavior &behavior) override;
+
+  const gd::Project &project;
+  gd::ArbitraryResourceWorker &worker;
+};
+
+gd::ResourceWorkerInObjectsWorker GD_CORE_API
+GetResourceWorkerOnObjects(const gd::Project &project, gd::ArbitraryResourceWorker &worker);

 }  // namespace gd
-
-#endif  // ARBITRARYRESOURCEWORKER_H
--- a/Core/GDCore/IDE/Project/ProjectResourcesAdder.cpp
+++ b/Core/GDCore/IDE/Project/ProjectResourcesAdder.cpp
@@ -9,6 +9,7 @@
 #include "GDCore/Project/Project.h"
 #include "GDCore/Tools/Localization.h"
 #include "GDCore/Tools/Log.h"
+#include "GDCore/IDE/ResourceExposer.h"

 using namespace std;

@@ -19,7 +20,7 @@ std::vector<gd::String> ProjectResourcesAdder::GetAllUseless(
  std::vector<gd::String> unusedResources;
  // Search for resources used in the project
  gd::ResourcesInUseHelper resourcesInUse;
-  project.ExposeResources(resourcesInUse);
+  gd::ResourceExposer::ExposeWholeProjectResources(project, resourcesInUse);
  std::set<gd::String>& usedResources = resourcesInUse.GetAll(resourceType);

  // Search all resources not used
--- a/Core/GDCore/IDE/Project/ProjectResourcesCopier.cpp
+++ b/Core/GDCore/IDE/Project/ProjectResourcesCopier.cpp
@@ -12,6 +12,7 @@
 #include "GDCore/Project/Project.h"
 #include "GDCore/Tools/Localization.h"
 #include "GDCore/Tools/Log.h"
+#include "GDCore/IDE/ResourceExposer.h"

 using namespace std;

@@ -26,7 +27,7 @@ bool ProjectResourcesCopier::CopyAllResourcesTo(
    bool preserveDirectoryStructure) {
  // Check if there are some resources with absolute filenames
  gd::ResourcesAbsolutePathChecker absolutePathChecker(fs);
-  originalProject.ExposeResources(absolutePathChecker);
+  gd::ResourceExposer::ExposeWholeProjectResources(originalProject, absolutePathChecker);

  auto projectDirectory = fs.DirNameFrom(originalProject.GetProjectFile());
  std::cout << "Copying all resources from " << projectDirectory << " to "
@@ -41,10 +42,10 @@ bool ProjectResourcesCopier::CopyAllResourcesTo(
      preserveAbsoluteFilenames);

  if (updateOriginalProject) {
-    originalProject.ExposeResources(resourcesMergingHelper);
+    gd::ResourceExposer::ExposeWholeProjectResources(originalProject, resourcesMergingHelper);
  } else {
    std::shared_ptr<gd::Project> project(new gd::Project(originalProject));
-    project->ExposeResources(resourcesMergingHelper);
+    gd::ResourceExposer::ExposeWholeProjectResources(*project, resourcesMergingHelper);
  }

  // Copy resources
--- a/Core/GDCore/IDE/Project/ResourcesInUseHelper.h
+++ b/Core/GDCore/IDE/Project/ResourcesInUseHelper.h
@@ -13,6 +13,7 @@

 #include "GDCore/IDE/Project/ArbitraryResourceWorker.h"
 #include "GDCore/String.h"
+#include "GDCore/IDE/ResourceExposer.h"

 namespace gd {

@@ -23,7 +24,7 @@ namespace gd {
 * Usage example:
 \code
 gd::ResourcesInUseHelper resourcesInUse;
-project.ExposeResources(resourcesInUse);
+gd::ResourceExposer::ExposeWholeProjectResources(project, resourcesInUse);

 //Get a set with the name of all images in the project:
 std::set<gd::String> & usedImages = resourcesInUse.GetAllImages();
--- a/Core/GDCore/IDE/ProjectBrowserHelper.cpp
+++ b/Core/GDCore/IDE/ProjectBrowserHelper.cpp
@@ -197,7 +197,7 @@ void ProjectBrowserHelper::ExposeProjectObjects(
  // Global objects
  worker.Launch(project);

-  // Layers objects
+  // Layout objects
  for (size_t i = 0; i < project.GetLayoutsCount(); i++) {
    worker.Launch(project.GetLayout(i));
  }
--- a/Core/GDCore/IDE/ProjectStripper.cpp
+++ b/Core/GDCore/IDE/ProjectStripper.cpp
@@ -11,6 +11,8 @@
 #include "GDCore/Project/ExternalLayout.h"
 #include "GDCore/Project/Layout.h"
 #include "GDCore/Project/Project.h"
+#include "GDCore/IDE/WholeProjectBrowser.h"
+#include "GDCore/IDE/Events/BehaviorDefaultFlagClearer.h"

 namespace gd {

@@ -19,6 +21,10 @@ void GD_CORE_API ProjectStripper::StripProjectForExport(gd::Project &project) {
  while (project.GetExternalEventsCount() > 0)
    project.RemoveExternalEvents(project.GetExternalEvents(0).GetName());

+  gd::BehaviorDefaultFlagClearer behaviorDefaultFlagClearer;
+  gd::WholeProjectBrowser wholeProjectBrowser;
+  wholeProjectBrowser.ExposeObjects(project, behaviorDefaultFlagClearer);
+
  for (unsigned int i = 0; i < project.GetLayoutsCount(); ++i) {
    project.GetLayout(i).GetObjectGroups().Clear();
    project.GetLayout(i).GetEvents().Clear();
--- a/Core/GDCore/IDE/ResourceExposer.cpp
+++ b/Core/GDCore/IDE/ResourceExposer.cpp
@@ -0,0 +1,101 @@
+/*
+ * GDevelop Core
+ * Copyright 2008-2016 Florian Rival (Florian.Rival@gmail.com). All rights
+ * reserved. This project is released under the MIT License.
+ */
+#include "ResourceExposer.h"
+
+#include "GDCore/IDE/Events/ArbitraryEventsWorker.h"
+#include "GDCore/IDE/EventsFunctionTools.h"
+#include "GDCore/IDE/Project/ArbitraryBehaviorSharedDataWorker.h"
+#include "GDCore/IDE/Project/ArbitraryEventBasedBehaviorsWorker.h"
+#include "GDCore/IDE/Project/ArbitraryEventsFunctionsWorker.h"
+#include "GDCore/IDE/Project/ArbitraryObjectsWorker.h"
+#include "GDCore/IDE/Project/ArbitraryResourceWorker.h"
+#include "GDCore/IDE/ProjectBrowserHelper.h"
+#include "GDCore/Project/EventsBasedBehavior.h"
+#include "GDCore/Project/EventsBasedObject.h"
+#include "GDCore/Project/EventsFunctionsExtension.h"
+#include "GDCore/Project/ExternalEvents.h"
+#include "GDCore/Project/Layout.h"
+#include "GDCore/Project/Project.h"
+#include "GDCore/Project/Effect.h"
+#include "GDCore/String.h"
+#include "GDCore/Extensions/Platform.h"
+#include "GDCore/Extensions/Metadata/MetadataProvider.h"
+#include "GDCore/Extensions/Metadata/EffectMetadata.h"
+
+namespace gd {
+
+void ResourceExposer::ExposeWholeProjectResources(gd::Project& project, gd::ArbitraryResourceWorker& worker) {
+  // See also gd::ProjectBrowserHelper::ExposeProjectEvents for a method that
+  // traverse the whole project (this time for events) and ExposeProjectEffects
+  // (this time for effects).
+
+  gd::ResourcesManager* resourcesManager = &(project.GetResourcesManager());
+
+  // Expose any project resources as files.
+  worker.ExposeResources(resourcesManager);
+  project.GetPlatformSpecificAssets().ExposeResources(worker);
+
+  // Expose event resources
+  auto eventWorker = gd::GetResourceWorkerOnEvents(project, worker);
+  gd::ProjectBrowserHelper::ExposeProjectEvents(
+    project, eventWorker);
+
+  // Expose object configuration resources
+  auto objectWorker = gd::GetResourceWorkerOnObjects(project, worker);
+  gd::ProjectBrowserHelper::ExposeProjectObjects(
+    project, objectWorker);
+
+  // Expose layer effect resources
+  for (std::size_t layoutIndex = 0; layoutIndex < project.GetLayoutsCount();
+       layoutIndex++) {
+    auto &layout = project.GetLayout(layoutIndex);
+
+    for (std::size_t layerIndex = 0; layerIndex < layout.GetLayersCount();
+         layerIndex++) {
+      auto &layer = layout.GetLayer(layerIndex);
+
+      auto &effects = layer.GetEffects();
+      for (size_t effectIndex = 0; effectIndex < effects.GetEffectsCount();
+           effectIndex++) {
+        auto &effect = effects.GetEffect(effectIndex);
+        gd::ResourceExposer::ExposeEffectResources(project.GetCurrentPlatform(),
+                                                   effect, worker);
+      }
+    }
+  }
+
+  // Expose loading screen background image if present
+  auto& loadingScreen = project.GetLoadingScreen();
+  if (loadingScreen.GetBackgroundImageResourceName() != "")
+    worker.ExposeImage(loadingScreen.GetBackgroundImageResourceName());
+}
+
+void ResourceExposer::ExposeEffectResources(
+    gd::Platform &platform, gd::Effect &effect,
+    gd::ArbitraryResourceWorker &worker) {
+  auto &effectMetadata =
+      MetadataProvider::GetEffectMetadata(platform, effect.GetEffectType());
+
+  for (auto &propertyPair : effectMetadata.GetProperties()) {
+    auto &propertyName = propertyPair.first;
+    auto &propertyDescriptor = propertyPair.second;
+
+    if (propertyDescriptor.GetType() == "resource" &&
+        propertyDescriptor.GetExtraInfo().size() > 0) {
+      auto &resourceType = propertyDescriptor.GetExtraInfo()[0];
+
+      const gd::String &resourceName = effect.GetStringParameter(propertyName);
+      gd::String potentiallyUpdatedResourceName = resourceName;
+      worker.ExposeResourceWithType(resourceType,
+                                    potentiallyUpdatedResourceName);
+      if (potentiallyUpdatedResourceName != resourceName) {
+        effect.SetStringParameter(propertyName, potentiallyUpdatedResourceName);
+      }
+    }
+  }
+}
+
+} // namespace gd
--- a/Core/GDCore/IDE/ResourceExposer.h
+++ b/Core/GDCore/IDE/ResourceExposer.h
@@ -0,0 +1,38 @@
+/*
+ * GDevelop Core
+ * Copyright 2008-2016 Florian Rival (Florian.Rival@gmail.com). All rights
+ * reserved. This project is released under the MIT License.
+ */
+#pragma once
+
+namespace gd {
+class Platform;
+class Project;
+class ArbitraryResourceWorker;
+class Effect;
+} // namespace gd
+
+namespace gd {
+
+/**
+ * \brief
+ */
+class GD_CORE_API ResourceExposer {
+public:
+  /**
+   * \brief Called ( e.g. during compilation ) so as to inventory internal
+   * resources, sometimes update their filename or any other work or resources.
+   *
+   * See WholeProjectRefactorer for the same thing for events.
+   *
+   * \see WholeProjectRefactorer
+   * \see ArbitraryResourceWorker
+   */
+  static void ExposeWholeProjectResources(gd::Project &project,
+                                          gd::ArbitraryResourceWorker &worker);
+
+  static void ExposeEffectResources(gd::Platform &platform, gd::Effect &effect,
+                                    gd::ArbitraryResourceWorker &worker);
+};
+
+} // namespace gd
--- a/Core/GDCore/IDE/WholeProjectRefactorer.cpp
+++ b/Core/GDCore/IDE/WholeProjectRefactorer.cpp
--- a/Core/GDCore/IDE/WholeProjectRefactorer.h
+++ b/Core/GDCore/IDE/WholeProjectRefactorer.h
@@ -456,6 +456,26 @@ class GD_CORE_API WholeProjectRefactorer {
      const gd::EventsFunctionsExtension& eventsFunctionsExtension,
      const gd::EventsBasedObject& eventsBasedObject);

+  /**
+   * \brief Remove all the instances from one layer.
+   */
+  static void RemoveLayer(gd::Project &project, gd::Layout &layout,
+                          const gd::String &layerName);
+
+  /**
+   * \brief Move all the instances from one layer into another.
+   */
+  static void MergeLayers(gd::Project &project, gd::Layout &layout,
+                          const gd::String &originLayerName,
+                          const gd::String &targetLayerName);
+
+  /**
+   * \brief Return the number of instances on the layer named \a layerName and
+   * all its associated layouts.
+   */
+  static size_t GetLayoutAndExternalLayoutLayerInstancesCount(
+      gd::Project &project, gd::Layout &layout, const gd::String &layerName);
+
  virtual ~WholeProjectRefactorer(){};

 private:
--- a/Core/GDCore/Project/Behavior.h
+++ b/Core/GDCore/Project/Behavior.h
@@ -23,11 +23,23 @@ namespace gd {
 class GD_CORE_API Behavior: public BehaviorConfigurationContainer {
 public:

-  Behavior(): BehaviorConfigurationContainer() {};
+  Behavior(): BehaviorConfigurationContainer(), isDefaultBehavior(false) {};
  Behavior(const gd::String& name_, const gd::String& type_)
-      : BehaviorConfigurationContainer(name_, type_) {};
+      : BehaviorConfigurationContainer(name_, type_),
+      isDefaultBehavior(false) {};
  virtual ~Behavior();
  virtual Behavior* Clone() const override { return new Behavior(*this); }
+
+  bool IsDefaultBehavior() const {
+    return isDefaultBehavior;
+  }
+
+  void SetDefaultBehavior(bool isDefaultBehavior_) {
+    isDefaultBehavior = isDefaultBehavior_;
+  }
+
+  private:
+  bool isDefaultBehavior;
 };

 }  // namespace gd
--- a/Core/GDCore/Project/CustomObjectConfiguration.cpp
+++ b/Core/GDCore/Project/CustomObjectConfiguration.cpp
@@ -153,6 +153,8 @@ void CustomObjectConfiguration::ExposeResources(gd::ArbitraryResourceWorker& wor
        worker.ExposeTileset(newPropertyValue);
      } else if (resourceType == "bitmapFont") {
        worker.ExposeBitmapFont(newPropertyValue);
+      } else if (resourceType == "model3D") {
+        worker.ExposeModel3D(newPropertyValue);
      }

      if (newPropertyValue != oldPropertyValue) {
--- a/Core/GDCore/Project/EventsBasedBehavior.h
+++ b/Core/GDCore/Project/EventsBasedBehavior.h
@@ -77,7 +77,7 @@ class GD_CORE_API EventsBasedBehavior: public AbstractEventsBasedEntity {
   * \brief Check if the behavior is private - it can't be used outside of its
   * extension.
   */
-  bool IsPrivate() { return isPrivate; }
+  bool IsPrivate() const { return isPrivate; }

  /**
   * \brief Set that the behavior is private - it can't be used outside of its
--- a/Core/GDCore/Project/EventsFunction.h
+++ b/Core/GDCore/Project/EventsFunction.h
@@ -201,7 +201,7 @@ class GD_CORE_API EventsFunction {
  /**
   * \brief Returns true if the function is private.
   */
-  bool IsPrivate() { return isPrivate; }
+  bool IsPrivate() const { return isPrivate; }

  /**
   * \brief Sets the privateness of the function.
--- a/Core/GDCore/Project/EventsFunctionsExtension.h
+++ b/Core/GDCore/Project/EventsFunctionsExtension.h
@@ -207,6 +207,13 @@ class GD_CORE_API EventsFunctionsExtension : public EventsFunctionsContainer {
    return dependencies;
  };

+  /**
+   * \brief Returns the list of dependencies.
+   */
+  const std::vector<gd::DependencyMetadata>& GetAllDependencies() const {
+    return dependencies;
+  };
+
  ///@}

  /** \name Serialization
--- a/Core/GDCore/Project/InitialInstance.cpp
+++ b/Core/GDCore/Project/InitialInstance.cpp
@@ -9,9 +9,9 @@
 #include "GDCore/Project/Layout.h"
 #include "GDCore/Project/Object.h"
 #include "GDCore/Project/Project.h"
+#include "GDCore/Project/PropertyDescriptor.h"
 #include "GDCore/Serialization/SerializerElement.h"
 #include "GDCore/Tools/UUID/UUID.h"
-#include "GDCore/Project/PropertyDescriptor.h"

 namespace gd {

@@ -21,12 +21,17 @@ InitialInstance::InitialInstance()
    : objectName(""),
      x(0),
      y(0),
+      z(0),
      angle(0),
+      rotationX(0),
+      rotationY(0),
      zOrder(0),
      layer(""),
-      personalizedSize(false),
+      customSize(false),
+      customDepth(false),
      width(0),
      height(0),
+      depth(0),
      locked(false),
      sealed(false),
      persistentUuid(UUID::MakeUuid4()) {}
@@ -35,11 +40,20 @@ void InitialInstance::UnserializeFrom(const SerializerElement& element) {
  SetObjectName(element.GetStringAttribute("name", "", "nom"));
  SetX(element.GetDoubleAttribute("x"));
  SetY(element.GetDoubleAttribute("y"));
+  SetZ(element.GetDoubleAttribute("z", 0));
  SetAngle(element.GetDoubleAttribute("angle"));
+  SetRotationX(element.GetDoubleAttribute("rotationX", 0));
+  SetRotationY(element.GetDoubleAttribute("rotationY", 0));
  SetHasCustomSize(
      element.GetBoolAttribute("customSize", false, "personalizedSize"));
  SetCustomWidth(element.GetDoubleAttribute("width"));
  SetCustomHeight(element.GetDoubleAttribute("height"));
+  if (element.HasChild("depth") || element.HasAttribute("depth")) {
+    SetHasCustomDepth(true);
+    SetCustomDepth(element.GetDoubleAttribute("depth"));
+  } else {
+    SetHasCustomDepth(false);
+  }
  SetZOrder(element.GetIntAttribute("zOrder", 0, "plan"));
  SetLayer(element.GetStringAttribute("layer"));
  SetLocked(element.GetBoolAttribute("locked", false));
@@ -53,9 +67,26 @@ void InitialInstance::UnserializeFrom(const SerializerElement& element) {
      element.GetChild("numberProperties", 0, "floatInfos");
  numberPropertiesElement.ConsiderAsArrayOf("property", "Info");
  for (std::size_t j = 0; j < numberPropertiesElement.GetChildrenCount(); ++j) {
-    gd::String name = numberPropertiesElement.GetChild(j).GetStringAttribute("name");
-    double value = numberPropertiesElement.GetChild(j).GetDoubleAttribute("value");
-    numberProperties[name] = value;
+    gd::String name =
+        numberPropertiesElement.GetChild(j).GetStringAttribute("name");
+    double value =
+        numberPropertiesElement.GetChild(j).GetDoubleAttribute("value");
+
+    // Compatibility with GD <= 5.1.164
+    if (name == "z") {
+      SetZ(value);
+    } else if (name == "rotationX") {
+      SetRotationX(value);
+    } else if (name == "rotationY") {
+      SetRotationY(value);
+    } else if (name == "depth") {
+      SetHasCustomDepth(true);
+      SetCustomDepth(value);
+    }
+    // end of compatibility code
+    else {
+      numberProperties[name] = value;
+    }
  }

  stringProperties.clear();
@@ -77,21 +108,26 @@ void InitialInstance::SerializeTo(SerializerElement& element) const {
  element.SetAttribute("name", GetObjectName());
  element.SetAttribute("x", GetX());
  element.SetAttribute("y", GetY());
+  if (GetZ() != 0) element.SetAttribute("z", GetZ());
  element.SetAttribute("zOrder", GetZOrder());
  element.SetAttribute("layer", GetLayer());
  element.SetAttribute("angle", GetAngle());
+  if (GetRotationX() != 0) element.SetAttribute("rotationX", GetRotationX());
+  if (GetRotationY() != 0) element.SetAttribute("rotationY", GetRotationY());
  element.SetAttribute("customSize", HasCustomSize());
  element.SetAttribute("width", GetCustomWidth());
  element.SetAttribute("height", GetCustomHeight());
+  if (HasCustomDepth()) element.SetAttribute("depth", GetCustomDepth());
  if (IsLocked()) element.SetAttribute("locked", IsLocked());
  if (IsSealed()) element.SetAttribute("sealed", IsSealed());

  if (persistentUuid.empty()) persistentUuid = UUID::MakeUuid4();
  element.SetStringAttribute("persistentUuid", persistentUuid);

-  SerializerElement& numberPropertiesElement = element.AddChild("numberProperties");
+  SerializerElement& numberPropertiesElement =
+      element.AddChild("numberProperties");
  numberPropertiesElement.ConsiderAsArrayOf("property");
-  for (const auto& property: numberProperties) {
+  for (const auto& property : numberProperties) {
    numberPropertiesElement.AddChild("property")
        .SetAttribute("name", property.first)
        .SetAttribute("value", property.second);
@@ -99,7 +135,7 @@ void InitialInstance::SerializeTo(SerializerElement& element) const {

  SerializerElement& stringPropElement = element.AddChild("stringProperties");
  stringPropElement.ConsiderAsArrayOf("property");
-  for (const auto& property: stringProperties) {
+  for (const auto& property : stringProperties) {
    stringPropElement.AddChild("property")
        .SetAttribute("name", property.first)
        .SetAttribute("value", property.second);
@@ -117,10 +153,12 @@ std::map<gd::String, gd::PropertyDescriptor>
 InitialInstance::GetCustomProperties(gd::Project& project, gd::Layout& layout) {
  // Find an object
  if (layout.HasObjectNamed(GetObjectName()))
-    return layout.GetObject(GetObjectName()).GetConfiguration()
+    return layout.GetObject(GetObjectName())
+        .GetConfiguration()
        .GetInitialInstanceProperties(*this, project, layout);
  else if (project.HasObjectNamed(GetObjectName()))
-    return project.GetObject(GetObjectName()).GetConfiguration()
+    return project.GetObject(GetObjectName())
+        .GetConfiguration()
        .GetInitialInstanceProperties(*this, project, layout);

  std::map<gd::String, gd::PropertyDescriptor> nothing;
@@ -132,10 +170,12 @@ bool InitialInstance::UpdateCustomProperty(const gd::String& name,
                                           gd::Project& project,
                                           gd::Layout& layout) {
  if (layout.HasObjectNamed(GetObjectName()))
-    return layout.GetObject(GetObjectName()).GetConfiguration()
+    return layout.GetObject(GetObjectName())
+        .GetConfiguration()
        .UpdateInitialInstanceProperty(*this, name, value, project, layout);
  else if (project.HasObjectNamed(GetObjectName()))
-    return project.GetObject(GetObjectName()).GetConfiguration()
+    return project.GetObject(GetObjectName())
+        .GetConfiguration()
        .UpdateInitialInstanceProperty(*this, name, value, project, layout);

  return false;
@@ -154,7 +194,8 @@ const gd::String& InitialInstance::GetRawStringProperty(
  return it != stringProperties.end() ? it->second : *badStringProperyValue;
 }

-void InitialInstance::SetRawDoubleProperty(const gd::String& name, double value) {
+void InitialInstance::SetRawDoubleProperty(const gd::String& name,
+                                           double value) {
  numberProperties[name] = value;
 }

--- a/Core/GDCore/Project/InitialInstance.h
+++ b/Core/GDCore/Project/InitialInstance.h
@@ -73,22 +73,52 @@ class GD_CORE_API InitialInstance {
  void SetY(double y_) { y = y_; }

  /**
-   * \brief Get the rotation of the instance, in radians.
+   * \brief Get the Z position of the instance
+   */
+  double GetZ() const { return z; }
+
+  /**
+   * \brief Set the Z position of the instance
+   */
+  void SetZ(double z_) { z = z_; }
+
+  /**
+   * \brief Get the rotation of the instance on Z axis, in radians.
   */
  double GetAngle() const { return angle; }

  /**
-   * \brief Set the rotation of the instance, in radians.
+   * \brief Set the rotation of the instance on Z axis, in radians.
   */
  void SetAngle(double angle_) { angle = angle_; }

  /**
-   * \brief Get the Z order of the instance.
+   * \brief Get the rotation of the instance on X axis, in radians.
+   */
+  double GetRotationX() const { return rotationX; }
+
+  /**
+   * \brief Set the rotation of the instance on X axis, in radians.
+   */
+  void SetRotationX(double rotationX_) { rotationX = rotationX_; }
+
+  /**
+   * \brief Get the rotation of the instance on Y axis, in radians.
+   */
+  double GetRotationY() const { return rotationY; }
+
+  /**
+   * \brief Set the rotation of the instance on Y axis, in radians.
+   */
+  void SetRotationY(double rotationY_) { rotationY = rotationY_; }
+
+  /**
+   * \brief Get the Z order of the instance (for a 2D object).
   */
  int GetZOrder() const { return zOrder; }

  /**
-   * \brief Set the Z order of the instance.
+   * \brief Set the Z order of the instance (for a 2D object).
   */
  void SetZOrder(int zOrder_) { zOrder = zOrder_; }

@@ -103,29 +133,51 @@ class GD_CORE_API InitialInstance {
  void SetLayer(const gd::String& layer_) { layer = layer_; }

  /**
-   * \brief Return true if the instance has a size which is different from its
-   * object default size.
+   * \brief Return true if the instance has a width/height which is different from its
+   * object default width/height. This is independent from `HasCustomDepth`.
   *
   * \see gd::Object
   */
-  bool HasCustomSize() const { return personalizedSize; }
+  bool HasCustomSize() const { return customSize; }

  /**
-   * \brief Set whether the instance has a size which is different from its
-   * object default size or not.
+   * \brief Return true if the instance has a depth which is different from its
+   * object default depth. This is independent from `HasCustomSize`.
   *
-   * \param hasCustomSize true if the size is different from the object's
-   * default size. \see gd::Object
+   * \see gd::Object
+   */
+  bool HasCustomDepth() const { return customDepth; }
+
+  /**
+   * \brief Set whether the instance has a width/height which is different from its
+   * object default width/height or not.
+   * This is independent from `SetHasCustomDepth`.
+   *
+   * \see gd::Object
   */
  void SetHasCustomSize(bool hasCustomSize_) {
-    personalizedSize = hasCustomSize_;
+    customSize = hasCustomSize_;
+  }
+
+  /**
+   * \brief Set whether the instance has a depth which is different from its
+   * object default depth or not.
+   * This is independent from `SetHasCustomSize`.
+   *
+   * \param hasCustomSize true if the depth is different from the object's
+   * default depth.
+   * \see gd::Object
+   */
+  void SetHasCustomDepth(bool hasCustomDepth_) {
+    customDepth = hasCustomDepth_;
  }

  double GetCustomWidth() const { return width; }
  void SetCustomWidth(double width_) { width = width_; }
-
  double GetCustomHeight() const { return height; }
  void SetCustomHeight(double height_) { height = height_; }
+  double GetCustomDepth() const { return depth; }
+  void SetCustomDepth(double depth_) { depth = depth_; }

  /**
   * \brief Return true if the instance is locked and cannot be moved in the
@@ -272,14 +324,19 @@ class GD_CORE_API InitialInstance {
      stringProperties;  ///< More data which can be used by the object

  gd::String objectName;  ///< Object name
-  double x;               ///< Object initial X position
-  double y;               ///< Object initial Y position
-  double angle;           ///< Object initial angle
-  int zOrder;             ///< Object initial Z order
-  gd::String layer;       ///< Object initial layer
-  bool personalizedSize;  ///< True if object has a custom size
-  double width;           ///< Object custom width
-  double height;          ///< Object custom height
+  double x;               ///< Instance X position
+  double y;               ///< Instance Y position
+  double z;               ///< Instance Z position (for a 3D object)
+  double angle;           ///< Instance angle on Z axis
+  double rotationX;       ///< Instance angle on X axis (for a 3D object)
+  double rotationY;       ///< Instance angle on Y axis (for a 3D object)
+  int zOrder;             ///< Instance Z order (for a 2D object)
+  gd::String layer;       ///< Instance layer
+  bool customSize;        ///< True if object has a custom width and height
+  bool customDepth;       ///< True if object has a custom depth
+  double width;           ///< Instance custom width
+  double height;          ///< Instance custom height
+  double depth;           ///< Instance custom depth
  gd::VariablesContainer initialVariables;  ///< Instance specific variables
  bool locked;                              ///< True if the instance is locked
  bool sealed;                              ///< True if the instance is sealed
--- a/Core/GDCore/Project/InitialInstancesContainer.cpp
+++ b/Core/GDCore/Project/InitialInstancesContainer.cpp
@@ -68,14 +68,14 @@ gd::InitialInstance& InitialInstancesContainer::InsertNewInitialInstance() {
 }

 void InitialInstancesContainer::RemoveInstanceIf(
-    std::function<bool(const gd::InitialInstance&)> predicat) {
+    std::function<bool(const gd::InitialInstance&)> predicate) {
  // Note that we can't use erase–remove idiom here because remove_if would
  // move the instances, and the container must guarantee that
  // iterators/pointers to instances always remain valid.
  for (std::list<gd::InitialInstance>::iterator it = initialInstances.begin(),
                                                end = initialInstances.end();
       it != end;) {
-    if (predicat(*it))
+    if (predicate(*it))
      it = initialInstances.erase(it);
    else
      ++it;
@@ -134,8 +134,19 @@ void InitialInstancesContainer::MoveInstancesToLayer(
  }
 }

+std::size_t InitialInstancesContainer::GetLayerInstancesCount(
+    const gd::String &layerName) const {
+  std::size_t count = 0;
+  for (const gd::InitialInstance &instance : initialInstances) {
+    if (instance.GetLayer() == layerName) {
+      count++;
+    }
+  }
+  return count;
+}
+
 bool InitialInstancesContainer::SomeInstancesAreOnLayer(
-    const gd::String& layerName) {
+    const gd::String& layerName) const {
  return std::any_of(initialInstances.begin(),
                     initialInstances.end(),
                     [&layerName](const InitialInstance& currentInstance) {
@@ -144,7 +155,7 @@ bool InitialInstancesContainer::SomeInstancesAreOnLayer(
 }

 bool InitialInstancesContainer::HasInstancesOfObject(
-    const gd::String& objectName) {
+    const gd::String& objectName) const {
  return std::any_of(initialInstances.begin(),
                     initialInstances.end(),
                     [&objectName](const InitialInstance& currentInstance) {
--- a/Core/GDCore/Project/InitialInstancesContainer.h
+++ b/Core/GDCore/Project/InitialInstancesContainer.h
@@ -4,8 +4,8 @@
 * reserved. This project is released under the MIT License.
 */

-#ifndef GDCORE_INITIALINSTANCESCONTAINER_H
-#define GDCORE_INITIALINSTANCESCONTAINER_H
+#pragma once
+
 #include <list>
 #include "GDCore/Project/InitialInstance.h"
 #include "GDCore/String.h"
@@ -54,7 +54,6 @@ class GD_CORE_API InitialInstancesContainer {
    return new InitialInstancesContainer(*this);
  };

-#if defined(GD_IDE_ONLY)
  /**
   * Must construct the class from the source
   * A such method is needed as the IDE may want to store copies of some
@@ -71,7 +70,6 @@ class GD_CORE_API InitialInstancesContainer {
   * from an object which is not a MyContainer"; } \endcode
   */
  void Create(const InitialInstancesContainer &source);
-#endif

  /** \name Instances management
   * Members functions related to managing the instances
@@ -100,7 +98,6 @@ class GD_CORE_API InitialInstancesContainer {
  void IterateOverInstancesWithZOrdering(InitialInstanceFunctor &func,
                                         const gd::String &layer);

-#if defined(GD_IDE_ONLY)
  /**
   * \brief Insert the specified \a instance into the list and return a
   * a reference to the newly added instance.
@@ -140,22 +137,27 @@ class GD_CORE_API InitialInstancesContainer {
  void RenameInstancesOfObject(const gd::String &oldName,
                               const gd::String &newName);

+  /**
+   * \brief Return the number of instances on the layer named \a layerName.
+   */
+  std::size_t GetLayerInstancesCount(const gd::String &layerName) const;
+
  /**
   * \brief Return true if there is at least one instance on the layer named \a
   * layerName.
   */
-  bool SomeInstancesAreOnLayer(const gd::String &layerName);
+  bool SomeInstancesAreOnLayer(const gd::String &layerName) const;

  /**
   * \brief Return true if there is at least one instance of the given object.
   */
-  bool HasInstancesOfObject(const gd::String &objectName);
+  bool HasInstancesOfObject(const gd::String &objectName) const;

  /**
   * \brief Remove all instances
   */
  void Clear();
-#endif
+
  ///@}

  /** \name Saving and loading
@@ -163,12 +165,10 @@ class GD_CORE_API InitialInstancesContainer {
   */
  ///@{

-#if defined(GD_IDE_ONLY)
  /**
   * \brief Serialize instances container.
   */
  virtual void SerializeTo(SerializerElement &element) const;
-#endif

  /**
   * \brief Unserialize the instances container.
@@ -178,7 +178,7 @@ class GD_CORE_API InitialInstancesContainer {

 private:
  void RemoveInstanceIf(
-      std::function<bool(const gd::InitialInstance &)> predicat);
+      std::function<bool(const gd::InitialInstance &)> predicate);

  std::list<gd::InitialInstance> initialInstances;

@@ -265,5 +265,3 @@ class GD_CORE_API HighestZOrderFinder : public gd::InitialInstanceFunctor {
 };

 }  // namespace gd
-
-#endif  // GDCORE_INITIALINSTANCESCONTAINER_H
--- a/Core/GDCore/Project/Layout.cpp
+++ b/Core/GDCore/Project/Layout.cpp
@@ -507,6 +507,81 @@ gd::String GD_CORE_API GetTypeOfObject(const gd::ObjectsContainer& project,
  return type;
 }

+void GD_CORE_API FilterBehaviorNamesFromObject(
+    const gd::Object &object, const gd::String &behaviorType,
+    std::vector<gd::String> &behaviorNames) {
+  for (size_t i = 0; i < behaviorNames.size(); i++) {
+    auto &behaviorName = behaviorNames[i];
+    if (!object.HasBehaviorNamed(behaviorName) ||
+        object.GetBehavior(behaviorName).GetTypeName() != behaviorType) {
+      behaviorNames.erase(behaviorNames.begin() + i);
+    }
+  }
+}
+
+std::vector<gd::String> GD_CORE_API GetBehaviorNamesInObjectOrGroup(
+    const gd::ObjectsContainer &project, const gd::ObjectsContainer &layout,
+    const gd::String &objectOrGroupName, const gd::String &behaviorType,
+    bool searchInGroups) {
+  // Search in objects
+  if (layout.HasObjectNamed(objectOrGroupName)) {
+    auto &object = layout.GetObject(objectOrGroupName);
+    auto behaviorNames = object.GetAllBehaviorNames();
+    FilterBehaviorNamesFromObject(object, behaviorType, behaviorNames);
+    return behaviorNames;
+  }
+  if (project.HasObjectNamed(objectOrGroupName)) {
+    auto &object = project.GetObject(objectOrGroupName);
+    auto behaviorNames = object.GetAllBehaviorNames();
+    FilterBehaviorNamesFromObject(object, behaviorType, behaviorNames);
+    return behaviorNames;
+  }
+
+  if (!searchInGroups) {
+    std::vector<gd::String> behaviorNames;
+    return behaviorNames;
+  }
+
+  // Search in groups
+  const gd::ObjectsContainer *container;
+  if (layout.GetObjectGroups().Has(objectOrGroupName)) {
+    container = &layout;
+  } else if (project.GetObjectGroups().Has(objectOrGroupName)) {
+    container = &project;
+  } else {
+    std::vector<gd::String> behaviorNames;
+    return behaviorNames;
+  }
+  const vector<gd::String> &groupsObjects =
+      container->GetObjectGroups().Get(objectOrGroupName).GetAllObjectsNames();
+  // Empty groups don't contain any behavior.
+  if (groupsObjects.empty()) {
+    std::vector<gd::String> behaviorNames;
+    return behaviorNames;
+  }
+
+  auto behaviorNames = GetBehaviorNamesInObjectOrGroup(
+      project, layout, groupsObjects[0], behaviorType, false);
+  for (size_t i = 1; i < groupsObjects.size(); i++) {
+    auto &objectName = groupsObjects[i];
+
+    if (layout.HasObjectNamed(objectName)) {
+      auto &object = layout.GetObject(objectName);
+      FilterBehaviorNamesFromObject(object, behaviorType, behaviorNames);
+      return behaviorNames;
+    }
+    if (project.HasObjectNamed(objectName)) {
+      auto &object = project.GetObject(objectName);
+      FilterBehaviorNamesFromObject(object, behaviorType, behaviorNames);
+      return behaviorNames;
+    }
+    if (behaviorNames.size() == 0) {
+      return behaviorNames;
+    }
+  }
+  return behaviorNames;
+}
+
 bool GD_CORE_API HasBehaviorInObjectOrGroup(const gd::ObjectsContainer &project,
                                            const gd::ObjectsContainer &layout,
                                            const gd::String &objectOrGroupName,
@@ -520,6 +595,56 @@ bool GD_CORE_API HasBehaviorInObjectOrGroup(const gd::ObjectsContainer &project,
    return project.GetObject(objectOrGroupName).HasBehaviorNamed(behaviorName);
  }

+  if (!searchInGroups) {
+    return false;
+  }
+
+  // Search in groups
+  const gd::ObjectsContainer *container;
+  if (layout.GetObjectGroups().Has(objectOrGroupName)) {
+    container = &layout;
+  } else if (project.GetObjectGroups().Has(objectOrGroupName)) {
+    container = &project;
+  } else {
+    return false;
+  }
+  const vector<gd::String> &groupsObjects =
+      container->GetObjectGroups().Get(objectOrGroupName).GetAllObjectsNames();
+  // Empty groups don't contain any behavior.
+  if (groupsObjects.empty()) {
+    return false;
+  }
+  // Check that all objects have the behavior.
+  for (auto &&object : groupsObjects) {
+    if (!HasBehaviorInObjectOrGroup(project, layout, object, behaviorName,
+                                    false)) {
+      return false;
+    }
+  }
+  return true;
+}
+
+bool GD_CORE_API IsDefaultBehavior(const gd::ObjectsContainer& project,
+                                         const gd::ObjectsContainer& layout,
+                                         gd::String objectOrGroupName,
+                                         gd::String behaviorName,
+                                         bool searchInGroups) {
+  // Search in objects
+  if (layout.HasObjectNamed(objectOrGroupName)) {
+    auto &object = layout.GetObject(objectOrGroupName);
+    return object.HasBehaviorNamed(behaviorName) &&
+           object.GetBehavior(behaviorName).IsDefaultBehavior();
+  }
+  if (project.HasObjectNamed(objectOrGroupName)) {
+    auto &object = project.GetObject(objectOrGroupName);
+    return object.HasBehaviorNamed(behaviorName) &&
+           object.GetBehavior(behaviorName).IsDefaultBehavior();
+  }
+
+  if (!searchInGroups) {
+    return false;
+  }
+
  // Search in groups
  const gd::ObjectsContainer *container;
  if (layout.GetObjectGroups().Has(objectOrGroupName)) {
@@ -537,7 +662,7 @@ bool GD_CORE_API HasBehaviorInObjectOrGroup(const gd::ObjectsContainer &project,
  }
  // Check that all objects have the same type.
  for (auto &&object : groupsObjects) {
-    if (!HasBehaviorInObjectOrGroup(project, layout, object, behaviorName,
+    if (!IsDefaultBehavior(project, layout, object, behaviorName,
                                    false)) {
      return false;
    }
@@ -545,6 +670,54 @@ bool GD_CORE_API HasBehaviorInObjectOrGroup(const gd::ObjectsContainer &project,
  return true;
 }

+gd::String GD_CORE_API GetTypeOfBehaviorInObjectOrGroup(const gd::ObjectsContainer& project,
+                                         const gd::ObjectsContainer& layout,
+                                         const gd::String& objectOrGroupName,
+                                         const gd::String& behaviorName,
+                                         bool searchInGroups) {
+  // Search in objects
+  if (layout.HasObjectNamed(objectOrGroupName)) {
+    auto &object = layout.GetObject(objectOrGroupName);
+    return object.HasBehaviorNamed(behaviorName) ?
+           object.GetBehavior(behaviorName).GetTypeName() : "";
+  }
+  if (project.HasObjectNamed(objectOrGroupName)) {
+    auto &object = project.GetObject(objectOrGroupName);
+    return object.HasBehaviorNamed(behaviorName) ?
+           object.GetBehavior(behaviorName).GetTypeName() : "";
+  }
+
+  if (!searchInGroups) {
+    return "";
+  }
+
+  // Search in groups
+  const gd::ObjectsContainer *container;
+  if (layout.GetObjectGroups().Has(objectOrGroupName)) {
+    container = &layout;
+  } else if (project.GetObjectGroups().Has(objectOrGroupName)) {
+    container = &project;
+  } else {
+    return "";
+  }
+  const vector<gd::String> &groupsObjects =
+      container->GetObjectGroups().Get(objectOrGroupName).GetAllObjectsNames();
+  // Empty groups don't contain any behavior.
+  if (groupsObjects.empty()) {
+    return "";
+  }
+  // Check that all objects have the behavior with the same type.
+  auto behaviorType = GetTypeOfBehaviorInObjectOrGroup(
+      project, layout, groupsObjects[0], behaviorName, false);
+  for (auto &&object : groupsObjects) {
+    if (GetTypeOfBehaviorInObjectOrGroup(project, layout, object, behaviorName,
+                                    false) != behaviorType) {
+      return "";
+    }
+  }
+  return behaviorType;
+}
+
 gd::String GD_CORE_API GetTypeOfBehavior(const gd::ObjectsContainer& project,
                                         const gd::ObjectsContainer& layout,
                                         gd::String name,
--- a/Core/GDCore/Project/Layout.h
+++ b/Core/GDCore/Project/Layout.h
@@ -443,13 +443,39 @@ gd::String GD_CORE_API GetTypeOfObject(const ObjectsContainer& game,
                                       gd::String objectName,
                                       bool searchInGroups = true);
 /**
- * \brief Check if an object or all object of a group has a behavior.
+ * \brief Check if an object or all objects of a group has a behavior.
 */
 bool GD_CORE_API HasBehaviorInObjectOrGroup(const gd::ObjectsContainer &project,
                                            const gd::ObjectsContainer &layout,
                                            const gd::String &objectOrGroupName,
                                            const gd::String &behaviorName,
                                            bool searchInGroups = true);
+/**
+ * \brief Get the names of behavior of a given type if an object or all objects of a group has it.
+ */
+std::vector<gd::String> GD_CORE_API GetBehaviorNamesInObjectOrGroup(
+    const gd::ObjectsContainer &project, const gd::ObjectsContainer &layout,
+    const gd::String &objectOrGroupName, const gd::String &behaviorType,
+    bool searchInGroups);
+
+/**
+ * \brief Check if a behavior is a default one or doesn't exist in an object or
+ * all objects of a group.
+ */
+bool GD_CORE_API IsDefaultBehavior(const gd::ObjectsContainer& project,
+                                   const gd::ObjectsContainer& layout,
+                                   gd::String objectOrGroupName,
+                                   gd::String behaviorName,
+                                   bool searchInGroups = true);
+
+/**
+ * \brief Get the type of a behavior if an object or all objects of a group has it.
+ */
+gd::String GD_CORE_API GetTypeOfBehaviorInObjectOrGroup(const gd::ObjectsContainer &project,
+                                            const gd::ObjectsContainer &layout,
+                                            const gd::String &objectOrGroupName,
+                                            const gd::String &behaviorName,
+                                            bool searchInGroups = true);
 /**
 * \brief Get a type from a behavior name
 * @return Type of the behavior.
--- a/Core/GDCore/Project/Object.cpp
+++ b/Core/GDCore/Project/Object.cpp
@@ -134,7 +134,6 @@ void Object::UnserializeFrom(gd::Project& project,

  objectVariables.UnserializeFrom(
      element.GetChild("variables", 0, "Variables"));
-  behaviors.clear();

  if (element.HasChild("effects")) {
    const SerializerElement& effectsElement = element.GetChild("effects");
@@ -210,6 +209,11 @@ void Object::SerializeTo(SerializerElement& element) const {
  std::vector<gd::String> allBehaviors = GetAllBehaviorNames();
  for (std::size_t i = 0; i < allBehaviors.size(); ++i) {
    const gd::Behavior& behavior = GetBehavior(allBehaviors[i]);
+    // Default behaviors are added at the object creation according to metadata.
+    // They don't need to be serialized.
+    if (behavior.IsDefaultBehavior()) {
+      continue;
+    }
    SerializerElement& behaviorElement = behaviorsElement.AddChild("behavior");

    behavior.SerializeTo(behaviorElement);
--- a/Core/GDCore/Project/Object.h
+++ b/Core/GDCore/Project/Object.h
@@ -127,6 +127,10 @@ class GD_CORE_API Object {
  /** \brief Return the tags of the object.
   */
  const gd::String& GetTags() const { return tags; }
+
+  /** \brief Shortcut to check if the object is a 3D object.
+   */
+  bool Is3DObject() const { return configuration->Is3DObject(); }
  ///@}

  /** \name Behaviors management
--- a/Core/GDCore/Project/ObjectConfiguration.cpp
+++ b/Core/GDCore/Project/ObjectConfiguration.cpp
@@ -20,7 +20,7 @@ namespace gd {

 ObjectConfiguration::~ObjectConfiguration() {}

-ObjectConfiguration::ObjectConfiguration() {}
+ObjectConfiguration::ObjectConfiguration(): is3DObject(false) {}

 std::map<gd::String, gd::PropertyDescriptor> ObjectConfiguration::GetProperties() const {
  std::map<gd::String, gd::PropertyDescriptor> nothing;
--- a/Core/GDCore/Project/ObjectConfiguration.h
+++ b/Core/GDCore/Project/ObjectConfiguration.h
@@ -61,12 +61,22 @@ class GD_CORE_API ObjectConfiguration {

  /** \brief Change the type of the object.
   */
-  void SetType(const gd::String& type_) { type = type_; }
+  void SetType(const gd::String& type_) {
+    type = type_;
+
+    // For now, as a shortcut, consider only the objects from the built-in 3D extension
+    // to be 3D object.
+    is3DObject = type.find("Scene3D::") == 0;
+  }

  /** \brief Return the type of the object.
   */
  const gd::String& GetType() const { return type; }

+  /** \brief Shortcut to check if the object is a 3D object.
+   */
+  bool Is3DObject() const { return is3DObject; }
+
  /** \name Object properties
   * Reading and updating object configuration properties
   */
@@ -170,6 +180,7 @@ class GD_CORE_API ObjectConfiguration {
 protected:
  gd::String type; ///< Which type of object is represented by this
                   ///< configuration.
+  bool is3DObject;

  /**
   * \brief Derived object configuration can redefine this method to load
--- a/Core/GDCore/Project/Project.cpp
+++ b/Core/GDCore/Project/Project.cpp
@@ -15,13 +15,12 @@
 #include <vector>

 #include "GDCore/CommonTools.h"
+#include "GDCore/Events/Parsers/GrammarTerminals.h"
 #include "GDCore/Extensions/Metadata/ExpressionMetadata.h"
 #include "GDCore/Extensions/Metadata/MetadataProvider.h"
 #include "GDCore/Extensions/Platform.h"
 #include "GDCore/Extensions/PlatformExtension.h"
-#include "GDCore/IDE/Events/UsedExtensionsFinder.h"
 #include "GDCore/IDE/PlatformManager.h"
-#include "GDCore/IDE/Project/ArbitraryResourceWorker.h"
 #include "GDCore/Project/CustomObjectConfiguration.h"
 #include "GDCore/Project/EventsFunctionsExtension.h"
 #include "GDCore/Project/ExternalEvents.h"
@@ -49,6 +48,11 @@ using namespace std;

 namespace gd {

+// By default, disallow unicode in identifiers, but this can be set to true
+// by the IDE. In the future, this will be set to true by default, keeping backward compatibility.
+// We keep it disabled by default to progressively ask users to test it in real projects.
+bool Project::allowUsageOfUnicodeIdentifierNames = false;
+
 Project::Project()
    : name(_("Project")),
      version("1.0.0"),
@@ -65,6 +69,8 @@ Project::Project()
      pixelsRounding(false),
      adaptGameResolutionAtRuntime(true),
      sizeOnStartupMode("adaptWidth"),
+      antialiasingMode("MSAA"),
+      isAntialisingEnabledOnMobile(false),
      projectUuid(""),
      useDeprecatedZeroAsDefaultZOrder(false),
      useExternalSourceFiles(false),
@@ -80,9 +86,47 @@ Project::~Project() {}

 void Project::ResetProjectUuid() { projectUuid = UUID::MakeUuid4(); }

-std::unique_ptr<gd::Object> Project::CreateObject(
-    const gd::String& type, const gd::String& name) const {
-  return gd::make_unique<Object>(name, type, CreateObjectConfiguration(type));
+std::unique_ptr<gd::Object>
+Project::CreateObject(const gd::String &objectType, const gd::String &name) const {
+  std::unique_ptr<gd::Object> object =
+      gd::make_unique<Object>(name, objectType, CreateObjectConfiguration(objectType));
+
+  auto &platform = GetCurrentPlatform();
+  auto &project = *this;
+  auto addDefaultBehavior =
+      [&platform,
+       &project,
+       &object,
+       &objectType](const gd::String& behaviorType) {
+    auto &behaviorMetadata =
+        gd::MetadataProvider::GetBehaviorMetadata(platform, behaviorType);
+    if (MetadataProvider::IsBadBehaviorMetadata(behaviorMetadata)) {
+      gd::LogWarning("Object: " + objectType + " has an unknown default behavior: " + behaviorType);
+      return;
+    }
+    auto* behavior = object->AddNewBehavior(project, behaviorType,
+                          behaviorMetadata.GetDefaultName());
+    behavior->SetDefaultBehavior(true);
+  };
+
+  if (Project::HasEventsBasedObject(objectType)) {
+    addDefaultBehavior("EffectCapability::EffectBehavior");
+    addDefaultBehavior("ResizableCapability::ResizableBehavior");
+    addDefaultBehavior("ScalableCapability::ScalableBehavior");
+    addDefaultBehavior("FlippableCapability::FlippableBehavior");
+  }
+  else {
+    auto &objectMetadata = gd::MetadataProvider::GetObjectMetadata(platform, objectType);
+    if (MetadataProvider::IsBadObjectMetadata(objectMetadata)) {
+      gd::LogWarning("Object: " + name + " has an unknown type: " + objectType);
+    }
+    for (auto &behaviorType : objectMetadata.GetDefaultBehaviors()) {
+      addDefaultBehavior(behaviorType);
+    }
+  }
+
+  
+  return std::move(object);
 }

 std::unique_ptr<gd::ObjectConfiguration> Project::CreateObjectConfiguration(
@@ -628,6 +672,10 @@ void Project::UnserializeFrom(const SerializerElement& element) {
  SetAdaptGameResolutionAtRuntime(
      propElement.GetBoolAttribute("adaptGameResolutionAtRuntime", false));
  SetSizeOnStartupMode(propElement.GetStringAttribute("sizeOnStartupMode", ""));
+  SetAntialiasingMode(
+      propElement.GetStringAttribute("antialiasingMode", "MSAA"));
+  SetAntialisingEnabledOnMobile(
+      propElement.GetBoolAttribute("antialisingEnabledOnMobile", false));
  SetProjectUuid(propElement.GetStringAttribute("projectUuid", ""));
  SetAuthor(propElement.GetChild("author", 0, "Auteur").GetValue().GetString());
  SetPackageName(propElement.GetStringAttribute("packageName"));
@@ -882,6 +930,9 @@ void Project::SerializeTo(SerializerElement& element) const {
  propElement.SetAttribute("adaptGameResolutionAtRuntime",
                           adaptGameResolutionAtRuntime);
  propElement.SetAttribute("sizeOnStartupMode", sizeOnStartupMode);
+  propElement.SetAttribute("antialiasingMode", antialiasingMode);
+  propElement.SetAttribute("antialisingEnabledOnMobile",
+                           isAntialisingEnabledOnMobile);
  propElement.SetAttribute("projectUuid", projectUuid);
  propElement.SetAttribute("folderProject", folderProject);
  propElement.SetAttribute("packageName", packageName);
@@ -987,58 +1038,57 @@ void Project::SerializeTo(SerializerElement& element) const {
        externalSourceFilesElement.AddChild("sourceFile"));
 }

-bool Project::ValidateName(const gd::String& name) {
+void Project::AllowUsageOfUnicodeIdentifierNames(bool enable) {
+  allowUsageOfUnicodeIdentifierNames = enable;
+}
+
+bool Project::IsNameSafe(const gd::String& name) {
  if (name.empty()) return false;

  if (isdigit(name[0])) return false;

-  gd::String allowedCharacters =
-      "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789_";
-  return !(name.find_first_not_of(allowedCharacters) != gd::String::npos);
+  if (!allowUsageOfUnicodeIdentifierNames) {
+    gd::String legacyAllowedCharacters =
+        "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789_";
+    return !(name.find_first_not_of(legacyAllowedCharacters) != gd::String::npos);
+  } else {
+    for (auto character : name) {
+      if (!GrammarTerminals::IsAllowedInIdentifier(character)) {
+        return false;
+      }
+    }
+
+    return true;
+  }
 }

-void Project::ExposeResources(gd::ArbitraryResourceWorker& worker) {
-  // See also gd::ProjectBrowserHelper::ExposeProjectEvents for a method that
-  // traverse the whole project (this time for events) and ExposeProjectEffects
-  // (this time for effects). Ideally, this method could be moved outside of
-  // gd::Project.
+gd::String Project::GetSafeName(const gd::String& name) {
+  if (name.empty()) return "Unnamed";

-  gd::ResourcesManager* resourcesManager = &GetResourcesManager();
+  gd::String newName = name;

-  // Add project resources
-  worker.ExposeResources(resourcesManager);
-  platformSpecificAssets.ExposeResources(worker);
+  if (isdigit(name[0])) newName = "_" + newName;

-  // Add layouts resources
-  for (std::size_t s = 0; s < GetLayoutsCount(); s++) {
-    for (std::size_t j = 0; j < GetLayout(s).GetObjectsCount();
-         ++j) {  // Add objects resources
-      GetLayout(s).GetObject(j).GetConfiguration().ExposeResources(worker);
-    }
+  gd::String legacyAllowedCharacters =
+      "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789_";

-    LaunchResourceWorkerOnEvents(*this, GetLayout(s).GetEvents(), worker);
-  }
-  // Add external events resources
-  for (std::size_t s = 0; s < GetExternalEventsCount(); s++) {
-    LaunchResourceWorkerOnEvents(
-        *this, GetExternalEvents(s).GetEvents(), worker);
-  }
-  // Add events functions extensions resources
-  for (std::size_t e = 0; e < GetEventsFunctionsExtensionsCount(); e++) {
-    auto& eventsFunctionsExtension = GetEventsFunctionsExtension(e);
-    for (auto&& eventsFunction : eventsFunctionsExtension.GetInternalVector()) {
-      LaunchResourceWorkerOnEvents(*this, eventsFunction->GetEvents(), worker);
+  for (size_t i = 0;i < newName.size();++i) {
+    // Note that iterating on the characters is not super efficient (O(n^2), which
+    // could be avoided with an iterator), but this function is not critical for performance
+    // (only used to generate a name when a user creates a new entity or rename one).
+    auto character = newName[i];
+    bool isAllowed =
+        allowUsageOfUnicodeIdentifierNames
+            ? GrammarTerminals::IsAllowedInIdentifier(character)
+            : legacyAllowedCharacters.find(character) != gd::String::npos;
+
+    // Replace all unallowed letters by an underscore.
+    if (!isAllowed) {
+      newName.replace(i, 1, '_');
    }
  }

-  // Add global objects resources
-  for (std::size_t j = 0; j < GetObjectsCount(); ++j) {
-    GetObject(j).GetConfiguration().ExposeResources(worker);
-  }
-
-  // Add loading screen background image if present
-  if (loadingScreen.GetBackgroundImageResourceName() != "")
-    worker.ExposeImage(loadingScreen.GetBackgroundImageResourceName());
+  return newName;
 }

 bool Project::HasSourceFile(gd::String name, gd::String language) const {
@@ -1113,6 +1163,8 @@ void Project::Init(const gd::Project& game) {
  pixelsRounding = game.pixelsRounding;
  adaptGameResolutionAtRuntime = game.adaptGameResolutionAtRuntime;
  sizeOnStartupMode = game.sizeOnStartupMode;
+  antialiasingMode = game.antialiasingMode;
+  isAntialisingEnabledOnMobile = game.isAntialisingEnabledOnMobile;
  projectUuid = game.projectUuid;
  useDeprecatedZeroAsDefaultZOrder = game.useDeprecatedZeroAsDefaultZOrder;

--- a/Core/GDCore/Project/Project.h
+++ b/Core/GDCore/Project/Project.h
@@ -383,6 +383,26 @@ class GD_CORE_API Project : public ObjectsContainer {
   */
  void SetPixelsRounding(bool enable) { pixelsRounding = enable; }

+  /**
+   * Return the antialiasing mode used by the game ("none" or "MSAA").
+   */
+  const gd::String& GetAntialiasingMode() const { return antialiasingMode; }
+
+  /**
+   * Set the antialiasing mode used by the game ("none" or "MSAA").
+   */
+  void SetAntialiasingMode(const gd::String& antialiasingMode_) { antialiasingMode = antialiasingMode_; }
+
+  /**
+   * Return true if antialising is enabled on mobiles.
+   */
+  bool IsAntialisingEnabledOnMobile() const { return isAntialisingEnabledOnMobile; }
+
+  /**
+   * Set whether antialising is enabled on mobiles or not.
+   */
+  void SetAntialisingEnabledOnMobile(bool enable) { isAntialisingEnabledOnMobile = enable; }
+
  /**
   * \brief Return if the project should set 0 as Z-order for objects created
   * from events (which is deprecated) - instead of the highest Z order that was
@@ -922,16 +942,6 @@ class GD_CORE_API Project : public ObjectsContainer {
   */
  ResourcesManager& GetResourcesManager() { return resourcesManager; }

-  /**
-   * \brief Called ( e.g. during compilation ) so as to inventory internal
-   * resources, sometimes update their filename or any other work or resources.
-   *
-   * See WholeProjectRefactorer for the same thing for events.
-   *
-   * \see WholeProjectRefactorer
-   * \see ArbitraryResourceWorker
-   */
-  void ExposeResources(gd::ArbitraryResourceWorker& worker);
  ///@}

  /** \name Variable management
@@ -955,15 +965,35 @@ class GD_CORE_API Project : public ObjectsContainer {

  ///@}

-  /** \name Other
+  /** \name Identifier names
   */
  ///@{

+  /**
+   * Check if unicode names are allowed in identifier names.
+   * \see IsNameSafe
+   * \see GetSafeName
+   */
+  static bool IsUsageOfUnicodeIdentifierNamesAllowed() { return allowUsageOfUnicodeIdentifierNames; };
+
+  /**
+   * Set if unicode names are allowed in identifier names.
+   * \see IsNameSafe
+   * \see GetSafeName
+   */
+  static void AllowUsageOfUnicodeIdentifierNames(bool enable);
+
  /**
   * Return true if \a name is valid (can be used safely for an object,
   * behavior, events function name, etc...).
   */
-  static bool ValidateName(const gd::String& name);
+  static bool IsNameSafe(const gd::String& name);
+
+  /**
+   * Return a name, based on the one passed in parameter, that can be safely used
+   * for an object, behavior, events function name, etc...
+   */
+  static gd::String GetSafeName(const gd::String& name);
  ///@}

  /** \name External source files
@@ -1040,6 +1070,8 @@ class GD_CORE_API Project : public ObjectsContainer {
  gd::String
      sizeOnStartupMode;   ///< How to adapt the game size to the screen. Can be
                           ///< "adaptWidth", "adaptHeight" or empty
+  gd::String antialiasingMode;
+  bool isAntialisingEnabledOnMobile;
  gd::String projectUuid;  ///< UUID useful to identify the game in online
                           ///< services or database that would require it.
  bool useDeprecatedZeroAsDefaultZOrder;  ///< If true, objects created from
@@ -1096,6 +1128,8 @@ class GD_CORE_API Project : public ObjectsContainer {
                                        ///< time the project was saved.
  mutable unsigned int gdBuildVersion;  ///< The GD build version used the last
                                        ///< time the project was saved.
+
+  static bool allowUsageOfUnicodeIdentifierNames;
 };

 }  // namespace gd
--- a/Core/GDCore/String.cpp
+++ b/Core/GDCore/String.cpp
@@ -686,6 +686,16 @@ String GD_CORE_API operator+(const char *lhs, const String &rhs)
    return str;
 }

+const String& GD_CORE_API operator||(const String& lhs, const String &rhs)
+{
+    return lhs.empty() ? rhs : lhs;
+}
+
+String GD_CORE_API operator||(String lhs, const char *rhs)
+{
+    return lhs.empty() ? rhs : lhs;
+}
+
 bool GD_CORE_API operator==( const String &lhs, const String &rhs )
 {
    return (lhs.compare(rhs) == 0);
--- a/Core/GDCore/String.h
+++ b/Core/GDCore/String.h
@@ -699,6 +699,10 @@ String GD_CORE_API operator+(String lhs, const char *rhs);
 */
 String GD_CORE_API operator+(const char *lhs, const String &rhs);

+const String& GD_CORE_API operator||(const String &lhs, const String &rhs);
+
+String GD_CORE_API operator||(String lhs, const char *rhs);
+
 /**
 * \}
 */
--- a/Core/tests/ArbitraryResourceWorker.cpp
+++ b/Core/tests/ArbitraryResourceWorker.cpp
@@ -22,6 +22,10 @@
 #include "DummyPlatform.h"
 #include "GDCore/Extensions/Builtin/SpriteExtension/SpriteObject.h"
 #include "catch.hpp"
+#include "GDCore/IDE/ResourceExposer.h"
+#include "GDCore/Project/Effect.h"
+#include "GDCore/Project/EventsFunctionsExtension.h"
+#include "GDCore/Project/ExternalEvents.h"

 class ArbitraryResourceWorkerTest : public gd::ArbitraryResourceWorker {
 public:
@@ -55,7 +59,7 @@ TEST_CASE("ArbitraryResourceWorker", "[common][resources]") {
        "res4", "path/to/file4.png", "audio");
    ArbitraryResourceWorkerTest worker;

-    project.ExposeResources(worker);
+    gd::ResourceExposer::ExposeWholeProjectResources(project, worker);
    REQUIRE(worker.files.size() == 4);
    REQUIRE(std::find(worker.files.begin(),
                      worker.files.end(),
@@ -78,7 +82,7 @@ TEST_CASE("ArbitraryResourceWorker", "[common][resources]") {

      worker.files.clear();
      worker.images.clear();
-      project.ExposeResources(worker);
+      gd::ResourceExposer::ExposeWholeProjectResources(project, worker);
      REQUIRE(worker.files.size() == 4);
      REQUIRE(worker.images.size() == 1);
      REQUIRE(worker.images[0] == "res1");
@@ -124,7 +128,7 @@ TEST_CASE("ArbitraryResourceWorker", "[common][resources]") {
    standardEvent.GetActions().Insert(instruction);
    layout.GetEvents().InsertEvent(standardEvent);

-    project.ExposeResources(worker);
+    gd::ResourceExposer::ExposeWholeProjectResources(project, worker);
    REQUIRE(worker.bitmapFonts.size() == 1);
    REQUIRE(worker.bitmapFonts[0] == "res3");
    REQUIRE(worker.images.size() == 1);
@@ -132,4 +136,207 @@ TEST_CASE("ArbitraryResourceWorker", "[common][resources]") {
    REQUIRE(worker.audios.size() == 1);
    REQUIRE(worker.audios[0] == "res4");
  }
+
+  SECTION("Can find resource usage in external events") {
+    gd::Platform platform;
+    gd::Project project;
+    SetupProjectWithDummyPlatform(project, platform);
+    project.GetResourcesManager().AddResource(
+        "res1", "path/to/file1.png", "image");
+    project.GetResourcesManager().AddResource(
+        "res2", "path/to/file2.png", "image");
+    project.GetResourcesManager().AddResource(
+        "res3", "path/to/file3.fnt", "bitmapFont");
+    project.GetResourcesManager().AddResource(
+        "res4", "path/to/file4.png", "audio");
+    ArbitraryResourceWorkerTest worker;
+
+    auto& externalEvents = project.InsertNewExternalEvents("MyExternalEvents", 0);
+
+    gd::StandardEvent standardEvent;
+    gd::Instruction instruction;
+    instruction.SetType("MyExtension::DoSomethingWithResources");
+    instruction.SetParametersCount(3);
+    instruction.SetParameter(0, "res3");
+    instruction.SetParameter(1, "res1");
+    instruction.SetParameter(2, "res4");
+    standardEvent.GetActions().Insert(instruction);
+    externalEvents.GetEvents().InsertEvent(standardEvent);
+
+    // MyExternalEvents doesn't need to be used in any layout events.
+
+    gd::ResourceExposer::ExposeWholeProjectResources(project, worker);
+    REQUIRE(worker.bitmapFonts.size() == 1);
+    REQUIRE(worker.bitmapFonts[0] == "res3");
+    REQUIRE(worker.images.size() == 1);
+    REQUIRE(worker.images[0] == "res1");
+    REQUIRE(worker.audios.size() == 1);
+    REQUIRE(worker.audios[0] == "res4");
+  }
+
+  SECTION("Can find resource usage in event-based functions") {
+    gd::Project project;
+    gd::Platform platform;
+    SetupProjectWithDummyPlatform(project, platform);
+
+    project.GetResourcesManager().AddResource(
+        "res1", "path/to/file1.png", "image");
+    project.GetResourcesManager().AddResource(
+        "res2", "path/to/file2.png", "image");
+    project.GetResourcesManager().AddResource(
+        "res3", "path/to/file3.png", "image");
+    ArbitraryResourceWorkerTest worker;
+
+    auto& extension = project.InsertNewEventsFunctionsExtension("MyEventExtention", 0);
+    auto& function = extension.InsertNewEventsFunction("MyFreeFunction", 0);
+    
+    gd::StandardEvent standardEvent;
+    gd::Instruction instruction;
+    instruction.SetType("MyExtension::DoSomethingWithResources");
+    instruction.SetParametersCount(3);
+    instruction.SetParameter(0, "res3");
+    instruction.SetParameter(1, "res1");
+    instruction.SetParameter(2, "res4");
+    standardEvent.GetActions().Insert(instruction);
+    function.GetEvents().InsertEvent(standardEvent);
+
+    // MyEventExtention::MyFreeFunction doesn't need to be actually used in events.
+
+    gd::ResourceExposer::ExposeWholeProjectResources(project, worker);
+    REQUIRE(worker.bitmapFonts.size() == 1);
+    REQUIRE(worker.bitmapFonts[0] == "res3");
+    REQUIRE(worker.images.size() == 1);
+    REQUIRE(worker.images[0] == "res1");
+    REQUIRE(worker.audios.size() == 1);
+    REQUIRE(worker.audios[0] == "res4");
+  }
+
+  SECTION("Can find resource usage in event-based behavior functions") {
+    gd::Project project;
+    gd::Platform platform;
+    SetupProjectWithDummyPlatform(project, platform);
+
+    project.GetResourcesManager().AddResource(
+        "res1", "path/to/file1.png", "image");
+    project.GetResourcesManager().AddResource(
+        "res2", "path/to/file2.png", "image");
+    project.GetResourcesManager().AddResource(
+        "res3", "path/to/file3.png", "image");
+    ArbitraryResourceWorkerTest worker;
+
+    auto& extension = project.InsertNewEventsFunctionsExtension("MyEventExtention", 0);
+    auto& behavior = extension.GetEventsBasedBehaviors().InsertNew("MyBehavior", 0);
+    auto& function = behavior.GetEventsFunctions().InsertNewEventsFunction("MyFunction", 0);
+    
+    gd::StandardEvent standardEvent;
+    gd::Instruction instruction;
+    instruction.SetType("MyExtension::DoSomethingWithResources");
+    instruction.SetParametersCount(3);
+    instruction.SetParameter(0, "res3");
+    instruction.SetParameter(1, "res1");
+    instruction.SetParameter(2, "res4");
+    standardEvent.GetActions().Insert(instruction);
+    function.GetEvents().InsertEvent(standardEvent);
+
+    // MyEventExtention::MyBehavior::MyFunction doesn't need to be actually used in events.
+
+    gd::ResourceExposer::ExposeWholeProjectResources(project, worker);
+    REQUIRE(worker.bitmapFonts.size() == 1);
+    REQUIRE(worker.bitmapFonts[0] == "res3");
+    REQUIRE(worker.images.size() == 1);
+    REQUIRE(worker.images[0] == "res1");
+    REQUIRE(worker.audios.size() == 1);
+    REQUIRE(worker.audios[0] == "res4");
+  }
+
+  SECTION("Can find resource usage in event-based object functions") {
+    gd::Project project;
+    gd::Platform platform;
+    SetupProjectWithDummyPlatform(project, platform);
+
+    project.GetResourcesManager().AddResource(
+        "res1", "path/to/file1.png", "image");
+    project.GetResourcesManager().AddResource(
+        "res2", "path/to/file2.png", "image");
+    project.GetResourcesManager().AddResource(
+        "res3", "path/to/file3.png", "image");
+    ArbitraryResourceWorkerTest worker;
+
+    auto& extension = project.InsertNewEventsFunctionsExtension("MyEventExtention", 0);
+    auto& object = extension.GetEventsBasedObjects().InsertNew("MyObject", 0);
+    auto& function = object.GetEventsFunctions().InsertNewEventsFunction("MyFunction", 0);
+    
+    gd::StandardEvent standardEvent;
+    gd::Instruction instruction;
+    instruction.SetType("MyExtension::DoSomethingWithResources");
+    instruction.SetParametersCount(3);
+    instruction.SetParameter(0, "res3");
+    instruction.SetParameter(1, "res1");
+    instruction.SetParameter(2, "res4");
+    standardEvent.GetActions().Insert(instruction);
+    function.GetEvents().InsertEvent(standardEvent);
+
+    // MyEventExtention::MyObject::MyFunction doesn't need to be actually used in events.
+
+    gd::ResourceExposer::ExposeWholeProjectResources(project, worker);
+    REQUIRE(worker.bitmapFonts.size() == 1);
+    REQUIRE(worker.bitmapFonts[0] == "res3");
+    REQUIRE(worker.images.size() == 1);
+    REQUIRE(worker.images[0] == "res1");
+    REQUIRE(worker.audios.size() == 1);
+    REQUIRE(worker.audios[0] == "res4");
+  }
+
+  SECTION("Can find resource usage in layer effects") {
+    gd::Project project;
+    gd::Platform platform;
+    SetupProjectWithDummyPlatform(project, platform);
+
+    project.GetResourcesManager().AddResource(
+        "res1", "path/to/file1.png", "image");
+    project.GetResourcesManager().AddResource(
+        "res2", "path/to/file2.png", "image");
+    project.GetResourcesManager().AddResource(
+        "res3", "path/to/file3.png", "image");
+    ArbitraryResourceWorkerTest worker;
+
+    auto& layout = project.InsertNewLayout("Scene", 0);
+    layout.InsertNewLayer("MyLayer", 0);
+    auto& layer = layout.GetLayer("MyLayer");
+    auto& effect = layer.GetEffects().InsertNewEffect("MyEffect", 0);
+    effect.SetEffectType("MyExtension::EffectWithResource");
+    effect.SetStringParameter("texture", "res1");
+
+    gd::ResourceExposer::ExposeWholeProjectResources(project, worker);
+    REQUIRE(worker.files.size() == 3);
+    REQUIRE(worker.images.size() == 1);
+    REQUIRE(worker.images[0] == "res1");
+  }
+
+  SECTION("Can find resource usage in object effects") {
+    gd::Project project;
+    gd::Platform platform;
+    SetupProjectWithDummyPlatform(project, platform);
+
+    project.GetResourcesManager().AddResource(
+        "res1", "path/to/file1.png", "image");
+    project.GetResourcesManager().AddResource(
+        "res2", "path/to/file2.png", "image");
+    project.GetResourcesManager().AddResource(
+        "res3", "path/to/file3.png", "image");
+    ArbitraryResourceWorkerTest worker;
+
+    auto& layout = project.InsertNewLayout("Scene", 0);
+    layout.InsertNewLayer("MyLayer", 0);
+    auto& layer = layout.GetLayer("MyLayer");
+    auto& object = layout.InsertNewObject(project, "MyExtension::Sprite", "MyObject", 0);
+    auto& effect = object.GetEffects().InsertNewEffect("MyEffect", 0);
+    effect.SetEffectType("MyExtension::EffectWithResource");
+    effect.SetStringParameter("texture", "res1");
+
+    gd::ResourceExposer::ExposeWholeProjectResources(project, worker);
+    REQUIRE(worker.files.size() == 3);
+    REQUIRE(worker.images.size() == 1);
+    REQUIRE(worker.images[0] == "res1");
+  }
 }
--- a/Core/tests/DummyPlatform.cpp
+++ b/Core/tests/DummyPlatform.cpp
@@ -113,17 +113,6 @@ void SetupProjectWithDummyPlatform(gd::Project& project,
  auto& baseObject = baseObjectExtension->AddObject<gd::ObjectConfiguration>(
      "", "Dummy Base Object", "Dummy Base Object", "");

-  // Add this expression for all objects. But it requires a "capability".
-  baseObject
-      .AddStrExpression("GetSomethingRequiringEffectCapability",
-                        "Get something, but this requires the effect capability for the object.",
-                        "",
-                        "",
-                        "")
-      .AddParameter("object", _("Object"), "")
-      .AddParameter("expression", _("Number parameter"))
-      .SetRequiresBaseObjectCapability("effect")
-      .SetFunctionName("getSomethingRequiringEffectCapability");
  baseObject
      .AddExpression("GetFromBaseExpression",
                     "This works on any object.",
@@ -133,6 +122,84 @@ void SetupProjectWithDummyPlatform(gd::Project& project,
      .AddParameter("object", _("Object"), "")
      .SetFunctionName("getFromBaseExpression");

+// Declare default behaviors that are used by event-based objects to avoid
+// warnings.
+{
+  std::shared_ptr<gd::PlatformExtension> extension =
+      std::shared_ptr<gd::PlatformExtension>(new gd::PlatformExtension);
+  extension
+      ->SetExtensionInformation("ResizableCapability",
+                               _("Resizable capability"),
+                               _("Change the object dimensions."),
+                               "", "");
+  gd::BehaviorMetadata& aut = extension->AddBehavior(
+      "ResizableBehavior",
+      _("Resizable capability"),
+      "Resizable",
+      _("Change the object dimensions."),
+      "", "", "",
+      std::make_shared<gd::Behavior>(),
+      std::make_shared<gd::BehaviorsSharedData>())
+    .SetHidden();
+  platform.AddExtension(extension);
+}
+{
+  std::shared_ptr<gd::PlatformExtension> extension =
+      std::shared_ptr<gd::PlatformExtension>(new gd::PlatformExtension);
+  extension
+      ->SetExtensionInformation("ScalableCapability",
+                               _("Scalable capability"),
+                               _("Change the object scale."),
+                               "", "");
+  gd::BehaviorMetadata& aut = extension->AddBehavior(
+      "ScalableBehavior",
+      _("Scalable capability"),
+      "Scale",
+      _("Change the object scale."),
+      "", "", "",
+      std::make_shared<gd::Behavior>(),
+      std::make_shared<gd::BehaviorsSharedData>())
+    .SetHidden();
+  platform.AddExtension(extension);
+}
+{
+  std::shared_ptr<gd::PlatformExtension> extension =
+      std::shared_ptr<gd::PlatformExtension>(new gd::PlatformExtension);
+  extension
+      ->SetExtensionInformation("FlippableCapability",
+                               _("Flippable capability"),
+                               _("Flip objects."),
+                               "", "");
+  gd::BehaviorMetadata& aut = extension->AddBehavior(
+      "FlippableBehavior",
+      _("Flippable capability"),
+      "Flippable",
+      _("Flip objects."),
+      "", "", "",
+      std::make_shared<gd::Behavior>(),
+      std::make_shared<gd::BehaviorsSharedData>())
+    .SetHidden();
+  platform.AddExtension(extension);
+}
+{
+  std::shared_ptr<gd::PlatformExtension> extension =
+      std::shared_ptr<gd::PlatformExtension>(new gd::PlatformExtension);
+  extension
+      ->SetExtensionInformation("EffectCapability",
+                               _("Effect capability"),
+                               _("Apply visual effects to objects."),
+                               "", "");
+  gd::BehaviorMetadata& aut = extension->AddBehavior(
+      "EffectBehavior",
+      _("Effect capability"),
+      "Effect",
+      _("Apply visual effects to objects."),
+      "", "", "",
+      std::make_shared<gd::Behavior>(),
+      std::make_shared<gd::BehaviorsSharedData>())
+    .SetHidden();
+  platform.AddExtension(extension);
+}
  // Create an extension with various stuff inside.
  std::shared_ptr<gd::PlatformExtension> extension =
      std::shared_ptr<gd::PlatformExtension>(new gd::PlatformExtension);
@@ -396,14 +463,53 @@ void SetupProjectWithDummyPlatform(gd::Project& project,
        gd::make_unique<gd::BehaviorsSharedData>());
  }

+  {
+    gd::BehaviorMetadata &effectBehavior =
+        extension
+            ->AddBehavior("EffectBehavior",
+                          _("Effect capability"),
+                          "Effect",
+                          _("Apply visual effects to objects."),
+                          "",
+                          "res/actions/effect24.png", "EffectBehavior",
+                          std::make_shared<gd::Behavior>(),
+                          std::make_shared<gd::BehaviorsSharedData>())
+            .SetHidden();
+
+    // Add this expression for the effect capability.
+    effectBehavior
+        .AddStrExpression("GetSomethingRequiringEffectCapability",
+                          "Get something, but this requires the effect "
+                          "capability for the object.",
+                          "",
+                          "",
+                          "")
+        .AddParameter("object", _("Object"), "")
+        .AddParameter("behavior", _("Behavior"), "EffectBehavior")
+        .AddParameter("expression", _("Number parameter"))
+        .SetFunctionName("getSomethingRequiringEffectCapability");
+  }
  {
    auto& object = extension
                       ->AddObject<gd::ObjectConfiguration>(
-                           "FakeObjectWithUnsupportedCapability",
-                           "FakeObjectWithUnsupportedCapability",
-                           "This is FakeObjectWithUnsupportedCapability",
+                           "FakeObjectWithDefaultBehavior",
+                           "FakeObjectWithDefaultBehavior",
+                           "This is FakeObjectWithDefaultBehavior",
                           "")
-                       .AddUnsupportedBaseObjectCapability("effect");
+                       .AddDefaultBehavior("MyExtension::EffectBehavior");
+  }
+
+  // Declare an event-based behavior to avoid warnings.
+  {
+    extension->AddBehavior("MyEventsBasedBehavior",
+                            "My event-based behavior",
+                            "MyEventsBasedBehavior",
+                            "Avoid warnings",
+                            "Group",
+                            "Icon.png",
+                            "MyEventsBasedBehavior",
+                            gd::make_unique<gd::Behavior>(),
+                            gd::make_unique<gd::BehaviorsSharedData>());
  }

  // Actions and expressions with several parameter types.
@@ -465,6 +571,17 @@ void SetupProjectWithDummyPlatform(gd::Project& project,
      .AddParameter("layerEffectParameterName", _("Parameter name"));
  }

+  {
+      auto& effect = extension
+      ->AddEffect("EffectWithResource")
+      .SetFullName("Effect with resource")
+      .MarkAsOnlyWorkingFor2D();
+      auto& effectProperties = effect.GetProperties();
+      effectProperties["texture"]
+      .SetType("resource")
+      .AddExtraInfo("image");
+  }
+
  platform.AddExtension(commonInstructionsExtension);
  platform.AddExtension(baseObjectExtension);
  platform.AddExtension(extension);
--- a/Core/tests/ExpressionCodeGenerator.cpp
+++ b/Core/tests/ExpressionCodeGenerator.cpp
@@ -24,13 +24,13 @@ TEST_CASE("ExpressionCodeGenerator", "[common][events]") {
  layout1.InsertNewObject(
      project, "MyExtension::Sprite", "MyOtherSpriteObject", 1);
  layout1.InsertNewObject(project,
-                          "MyExtension::FakeObjectWithUnsupportedCapability",
-                          "MyFakeObjectWithUnsupportedCapability",
+                          "MyExtension::FakeObjectWithDefaultBehavior",
+                          "FakeObjectWithDefaultBehavior",
                          2);
  auto &group = layout1.GetObjectGroups().InsertNew("AllObjects");
  group.AddObject("MySpriteObject");
  group.AddObject("MyOtherSpriteObject");
-  group.AddObject("MyFakeObjectWithUnsupportedCapability");
+  group.AddObject("FakeObjectWithDefaultBehavior");

  gd::ExpressionParser2 parser;

@@ -342,7 +342,7 @@ TEST_CASE("ExpressionCodeGenerator", "[common][events]") {
    SECTION("supported capability") {
      // Capability is supported, so the expression is valid.
      auto node = parser.ParseExpression(
-          "MySpriteObject.GetSomethingRequiringEffectCapability(123)");
+          "FakeObjectWithDefaultBehavior.Effect::GetSomethingRequiringEffectCapability(123)");
      gd::ExpressionCodeGenerator expressionCodeGenerator("string",
                                                          "",
                                                          codeGenerator,
@@ -352,12 +352,12 @@ TEST_CASE("ExpressionCodeGenerator", "[common][events]") {
      node->Visit(expressionCodeGenerator);
      REQUIRE(
          expressionCodeGenerator.GetOutput() ==
-          "MySpriteObject.getSomethingRequiringEffectCapability(123) ?? \"\"");
+          "FakeObjectWithDefaultBehavior::Effect.getSomethingRequiringEffectCapability(123) ?? \"\"");
    }
    SECTION("unsupported capability") {
      // Capability is not supported, so the expression is not even valid.
      auto node =
-          parser.ParseExpression("MyFakeObjectWithUnsupportedCapability."
+          parser.ParseExpression("MySpriteObject::Effect."
                                 "GetSomethingRequiringEffectCapability(123)");
      gd::ExpressionCodeGenerator expressionCodeGenerator("string",
                                                          "",
@@ -366,14 +366,16 @@ TEST_CASE("ExpressionCodeGenerator", "[common][events]") {

      REQUIRE(node);
      node->Visit(expressionCodeGenerator);
-      REQUIRE(expressionCodeGenerator.GetOutput() == "\"\"");
+      REQUIRE(
+        expressionCodeGenerator.GetOutput() ==
+        "/* Error during generation, function not found: GetSomethingRequiringEffectCapability */ \"\"");
    }
    SECTION("group with partial support") {
      // We use a group, capability is supported only by one object of the
      // group. The expression itself is valid, but code generation should skip
      // the objects with unsupported capability.
      auto node = parser.ParseExpression(
-          "AllObjects.GetSomethingRequiringEffectCapability(123)");
+          "AllObjects.Effect::GetSomethingRequiringEffectCapability(123)");
      gd::ExpressionCodeGenerator expressionCodeGenerator("string",
                                                          "",
                                                          codeGenerator,
@@ -381,10 +383,13 @@ TEST_CASE("ExpressionCodeGenerator", "[common][events]") {

      REQUIRE(node);
      node->Visit(expressionCodeGenerator);
-      REQUIRE(
-          expressionCodeGenerator.GetOutput() ==
-          "MyOtherSpriteObject.getSomethingRequiringEffectCapability(123) ?? "
-          "MySpriteObject.getSomethingRequiringEffectCapability(123) ?? \"\"");
+      REQUIRE(expressionCodeGenerator.GetOutput() ==
+              "FakeObjectWithDefaultBehavior::Effect."
+              "getSomethingRequiringEffectCapability(123) ?? "
+              "MyOtherSpriteObject::Effect."
+              "getSomethingRequiringEffectCapability(123) ?? "
+              "MySpriteObject::Effect.getSomethingRequiringEffectCapability("
+              "123) ?? \"\"");
    }
  }
  SECTION("Function name") {
--- a/Core/tests/ExpressionParser2.cpp
+++ b/Core/tests/ExpressionParser2.cpp
@@ -21,16 +21,18 @@ TEST_CASE("ExpressionParser2", "[common][events]") {
  SetupProjectWithDummyPlatform(project, platform);
  auto &layout1 = project.InsertNewLayout("Layout1", 0);

-  auto &myObject = layout1.InsertNewObject(project, "BuiltinObject", "MyObject", 0);
+  // Create an instance of BuiltinObject.
+  // This is not possible in practice.
+  auto &myObject = layout1.InsertNewObject(project, "", "MyObject", 0);
  myObject.AddNewBehavior(project, "MyExtension::MyBehavior", "MyBehavior");

  auto &myGroup = layout1.GetObjectGroups().InsertNew("MyGroup", 0);
  myGroup.AddObject(myObject.GetName());
-  
+
  layout1.InsertNewObject(project, "MyExtension::Sprite", "MySpriteObject", 1);
  layout1.InsertNewObject(project,
-                          "MyExtension::FakeObjectWithUnsupportedCapability",
-                          "MyFakeObjectWithUnsupportedCapability",
+                          "MyExtension::FakeObjectWithDefaultBehavior",
+                          "FakeObjectWithDefaultBehavior",
                          2);

  gd::ExpressionParser2 parser;
@@ -340,6 +342,20 @@ TEST_CASE("ExpressionParser2", "[common][events]") {
              "Cannot find an expression with this name: Idontexist\n"
              "Double check that you've not made any typo in the name.");
    }
+    {
+      auto node = parser.ParseExpression("🅸🅳🅾🅽🆃🅴🆇🅸🆂🆃😄(\"hello\"");
+      REQUIRE(node != nullptr);
+
+      gd::ExpressionValidator validator(platform, project, layout1, "string");
+      node->Visit(validator);
+      REQUIRE(validator.GetFatalErrors().size() == 2);
+      REQUIRE(validator.GetFatalErrors()[0]->GetMessage() ==
+              "The list of parameters is not terminated. Add a closing "
+              "parenthesis to end the parameters.");
+      REQUIRE(validator.GetFatalErrors()[1]->GetMessage() ==
+              "Cannot find an expression with this name: 🅸🅳🅾🅽🆃🅴🆇🅸🆂🆃😄\n"
+              "Double check that you've not made any typo in the name.");
+    }
    {
      auto node = parser.ParseExpression("=\"test\"");
      REQUIRE(node != nullptr);
@@ -694,6 +710,17 @@ TEST_CASE("ExpressionParser2", "[common][events]") {
              "You must enter a number.");
      REQUIRE(validator.GetFatalErrors()[0]->GetStartPosition() == 0);
    }
+    {
+      auto node = parser.ParseExpression("ab😊d");
+      REQUIRE(node != nullptr);
+
+      gd::ExpressionValidator validator(platform, project, layout1, "number");
+      node->Visit(validator);
+      REQUIRE(validator.GetFatalErrors().size() == 1);
+      REQUIRE(validator.GetFatalErrors()[0]->GetMessage() ==
+              "You must enter a number.");
+      REQUIRE(validator.GetFatalErrors()[0]->GetStartPosition() == 0);
+    }
    {
      auto node = parser.ParseExpression("abcd[0]");
      REQUIRE(node != nullptr);
@@ -917,6 +944,26 @@ TEST_CASE("ExpressionParser2", "[common][events]") {
      node->Visit(validator);
      REQUIRE(validator.GetFatalErrors().size() == 0);
    }
+    {
+      auto node = parser.ParseExpression("😅");
+      REQUIRE(node != nullptr);
+      auto &identifierNode = dynamic_cast<gd::IdentifierNode &>(*node);
+      REQUIRE(identifierNode.identifierName == "😅");
+
+      gd::ExpressionValidator validator(platform, project, layout1, "object");
+      node->Visit(validator);
+      REQUIRE(validator.GetFatalErrors().size() == 0);
+    }
+    {
+      auto node = parser.ParseExpression("中文");
+      REQUIRE(node != nullptr);
+      auto &identifierNode = dynamic_cast<gd::IdentifierNode &>(*node);
+      REQUIRE(identifierNode.identifierName == "中文");
+
+      gd::ExpressionValidator validator(platform, project, layout1, "object");
+      node->Visit(validator);
+      REQUIRE(validator.GetFatalErrors().size() == 0);
+    }

    {
      auto node = parser.ParseExpression("Hello World 1");
@@ -1092,6 +1139,46 @@ TEST_CASE("ExpressionParser2", "[common][events]") {
      REQUIRE(textNode.text == "2");
      REQUIRE(identifierNode.identifierName == "three");
    }
+    SECTION("identifier parameter (unicode)") {
+      auto node = parser.ParseExpression(
+          "WhateverObject.WhateverBehavior::WhateverFunction(1, \"2\", 😄)");
+      REQUIRE(node != nullptr);
+      auto &functionNode = dynamic_cast<gd::FunctionCallNode &>(*node);
+      REQUIRE(functionNode.functionName == "WhateverFunction");
+      REQUIRE(functionNode.objectName == "WhateverObject");
+      REQUIRE(functionNode.behaviorName == "WhateverBehavior");
+      REQUIRE(functionNode.parameters.size() == 3);
+      auto &numberNode =
+          dynamic_cast<gd::NumberNode &>(*functionNode.parameters[0]);
+      auto &textNode =
+          dynamic_cast<gd::TextNode &>(*functionNode.parameters[1]);
+      auto &identifierNode =
+          dynamic_cast<gd::IdentifierNode &>(*functionNode.parameters[2]);
+
+      REQUIRE(numberNode.number == "1");
+      REQUIRE(textNode.text == "2");
+      REQUIRE(identifierNode.identifierName == "😄");
+    }
+    SECTION("unicode for object, behavior and function") {
+      auto node = parser.ParseExpression(
+          "🧸.🗣️::🔔(1, \"2\", 😄)");
+      REQUIRE(node != nullptr);
+      auto &functionNode = dynamic_cast<gd::FunctionCallNode &>(*node);
+      REQUIRE(functionNode.functionName == "🔔");
+      REQUIRE(functionNode.objectName == "🧸");
+      REQUIRE(functionNode.behaviorName == "🗣️");
+      REQUIRE(functionNode.parameters.size() == 3);
+      auto &numberNode =
+          dynamic_cast<gd::NumberNode &>(*functionNode.parameters[0]);
+      auto &textNode =
+          dynamic_cast<gd::TextNode &>(*functionNode.parameters[1]);
+      auto &identifierNode =
+          dynamic_cast<gd::IdentifierNode &>(*functionNode.parameters[2]);
+
+      REQUIRE(numberNode.number == "1");
+      REQUIRE(textNode.text == "2");
+      REQUIRE(identifierNode.identifierName == "😄");
+    }
  }

  SECTION("Valid function calls ('number|string' type)") {
@@ -1669,7 +1756,7 @@ TEST_CASE("ExpressionParser2", "[common][events]") {
      auto &identifierNode = dynamic_cast<gd::IdentifierNode &>(*node);
      REQUIRE(identifierNode.identifierName == "myVariable");
      REQUIRE(identifierNode.childIdentifierName == "myChild");
-      
+
      gd::ExpressionValidator validator(platform, project, layout1, "scenevar");
      node->Visit(validator);
      REQUIRE(validator.GetFatalErrors().size() == 0);
@@ -1766,14 +1853,14 @@ TEST_CASE("ExpressionParser2", "[common][events]") {
      REQUIRE(identifierObject2Node.identifierName == "MyObject2");
      REQUIRE(variable1Node.identifierName == "MyVar1");
      REQUIRE(variable2Node.identifierName == "MyVar2");
-      
+
      auto variable1ObjectName = gd::ExpressionVariableOwnerFinder::GetObjectName(
          platform, project, layout1, "", variable1Node);
      REQUIRE(variable1ObjectName == "MyObject1");
      auto variable2ObjectName = gd::ExpressionVariableOwnerFinder::GetObjectName(
          platform, project, layout1, "", variable2Node);
      REQUIRE(variable2ObjectName == "MyObject2");
-      
+
      gd::ExpressionValidator validator(platform, project, layout1, "string");
      node->Visit(validator);
      REQUIRE(validator.GetFatalErrors().size() == 0);
@@ -1797,14 +1884,14 @@ TEST_CASE("ExpressionParser2", "[common][events]") {
      REQUIRE(identifierObject1Node.identifierName == "MyObject1");
      REQUIRE(variable1Node.identifierName == "MyVar1");
      REQUIRE(variable2Node.identifierName == "MyVar2");
-      
+
      auto variable1ObjectName = gd::ExpressionVariableOwnerFinder::GetObjectName(
          platform, project, layout1, "", variable1Node);
      REQUIRE(variable1ObjectName == "MyObject1");
      auto variable2ObjectName = gd::ExpressionVariableOwnerFinder::GetObjectName(
          platform, project, layout1, "", variable2Node);
      REQUIRE(variable2ObjectName == "MyObject1");
-      
+
      gd::ExpressionValidator validator(platform, project, layout1, "string");
      node->Visit(validator);
      REQUIRE(validator.GetFatalErrors().size() == 0);
@@ -1821,11 +1908,11 @@ TEST_CASE("ExpressionParser2", "[common][events]") {
          dynamic_cast<gd::IdentifierNode &>(*functionNode.parameters[0]);

      REQUIRE(variable1Node.identifierName == "MyVar1");
-      
+
      auto variable1ObjectName = gd::ExpressionVariableOwnerFinder::GetObjectName(
          platform, project, layout1, "MySpriteObject", variable1Node);
      REQUIRE(variable1ObjectName == "MySpriteObject");
-      
+
      gd::ExpressionValidator validator(platform, project, layout1, "number");
      node->Visit(validator);
      REQUIRE(validator.GetFatalErrors().size() == 0);
@@ -1843,11 +1930,11 @@ TEST_CASE("ExpressionParser2", "[common][events]") {

      REQUIRE(variable1Node.identifierName == "MyVar1");
      REQUIRE(variable1Node.childIdentifierName == "MyChild");
-      
+
      auto variable1ObjectName = gd::ExpressionVariableOwnerFinder::GetObjectName(
          platform, project, layout1, "MySpriteObject", variable1Node);
      REQUIRE(variable1ObjectName == "MySpriteObject");
-      
+
      gd::ExpressionValidator validator(platform, project, layout1, "number");
      node->Visit(validator);
      REQUIRE(validator.GetFatalErrors().size() == 0);
@@ -1899,29 +1986,29 @@ TEST_CASE("ExpressionParser2", "[common][events]") {
  }

  SECTION(
-      "Valid function call with an object expression requiring a capability") {
+      "Valid function call with a default behavior") {
    auto node = parser.ParseExpression(
-        "MySpriteObject.GetSomethingRequiringEffectCapability(123)");
+        "FakeObjectWithDefaultBehavior.Effect::GetSomethingRequiringEffectCapability(123)");
    REQUIRE(node != nullptr);

    gd::ExpressionValidator validator(platform, project, layout1, "string");
    node->Visit(validator);
-    REQUIRE(validator.GetFatalErrors().size() == 0);
+    REQUIRE(validator.GetAllErrors().size() == 0);
  }

  SECTION(
-      "Invalid function call with an object expression requiring a "
-      "capability") {
+      "Invalid function call with an object that doesn't have a default behavior") {
    auto node =
-        parser.ParseExpression("MyFakeObjectWithUnsupportedCapability."
+        parser.ParseExpression("MySpriteObject.Effect::"
                               "GetSomethingRequiringEffectCapability(123)");
    REQUIRE(node != nullptr);

    gd::ExpressionValidator validator(platform, project, layout1, "string");
    node->Visit(validator);
-    REQUIRE(validator.GetFatalErrors().size() == 1);
-    REQUIRE(validator.GetFatalErrors()[0]->GetMessage() ==
-            "This expression exists, but it can't be used on this object.");
+    REQUIRE(validator.GetFatalErrors().size() == 0);
+    REQUIRE(validator.GetAllErrors().size() == 1);
+    REQUIRE(validator.GetAllErrors()[0]->GetMessage() ==
+            "This behavior is not attached to this object.");
  }

  SECTION("Fuzzy/random tests") {
--- a/Core/tests/Layout.cpp
+++ b/Core/tests/Layout.cpp
@@ -0,0 +1,133 @@
+/*
+ * GDevelop Core
+ * Copyright 2008-2023 Florian Rival (Florian.Rival@gmail.com). All rights
+ * reserved. This project is released under the MIT License.
+ */
+/**
+ * @file Tests covering layout content helper methods.
+ */
+#include "GDCore/Project/Layout.h"
+#include "DummyPlatform.h"
+#include "GDCore/CommonTools.h"
+#include "GDCore/Extensions/Platform.h"
+#include "GDCore/Project/Object.h"
+#include "GDCore/Project/ObjectsContainer.h"
+#include "GDCore/Project/Project.h"
+#include "catch.hpp"
+
+using namespace gd;
+
+namespace {
+
+void SetupProject(gd::Project &project, gd::Platform &platform){
+
+};
+} // namespace
+
+TEST_CASE("Layout", "[common]") {
+
+  SECTION("Find the type of a behavior in a object") {
+    gd::Platform platform;
+    gd::Project project;
+    SetupProjectWithDummyPlatform(project, platform);
+
+    gd::Layout &layout = project.InsertNewLayout("Scene", 0);
+    gd::Object &object =
+        layout.InsertNewObject(project, "MyExtension::Sprite", "MyObject", 0);
+    object.AddNewBehavior(project, "MyExtension::MyBehavior", "MyBehavior");
+
+    REQUIRE(GetTypeOfBehaviorInObjectOrGroup(project, layout, "MyObject",
+                                             "MyBehavior", true) ==
+            "MyExtension::MyBehavior");
+  }
+
+  SECTION("Give an empty type for an object that doesn't have the behavior") {
+    gd::Platform platform;
+    gd::Project project;
+    SetupProjectWithDummyPlatform(project, platform);
+
+    gd::Layout &layout = project.InsertNewLayout("Scene", 0);
+    gd::Object &object =
+        layout.InsertNewObject(project, "MyExtension::Sprite", "MyObject", 0);
+
+    REQUIRE(GetTypeOfBehaviorInObjectOrGroup(project, layout, "MyObject",
+                                             "MyBehavior", true) == "");
+  }
+
+  SECTION("Find the type of a behavior in a group") {
+    gd::Platform platform;
+    gd::Project project;
+    SetupProjectWithDummyPlatform(project, platform);
+
+    gd::Layout &layout = project.InsertNewLayout("Scene", 0);
+    gd::Object &object1 =
+        layout.InsertNewObject(project, "MyExtension::Sprite", "MyObject1", 0);
+    object1.AddNewBehavior(project, "MyExtension::MyBehavior", "MyBehavior");
+    gd::Object &object2 =
+        layout.InsertNewObject(project, "MyExtension::Sprite", "MyObject2", 0);
+    object2.AddNewBehavior(project, "MyExtension::MyBehavior", "MyBehavior");
+
+    auto &group = layout.GetObjectGroups().InsertNew("MyGroup", 0);
+    group.AddObject(object1.GetName());
+    group.AddObject(object2.GetName());
+
+    REQUIRE(GetTypeOfBehaviorInObjectOrGroup(project, layout, "MyGroup",
+                                             "MyBehavior", true) ==
+            "MyExtension::MyBehavior");
+  }
+
+  SECTION("Give an empty type for a group with an object missing the behavior") {
+    gd::Platform platform;
+    gd::Project project;
+    SetupProjectWithDummyPlatform(project, platform);
+
+    gd::Layout &layout = project.InsertNewLayout("Scene", 0);
+    gd::Object &object1 =
+        layout.InsertNewObject(project, "MyExtension::Sprite", "MyObject1", 0);
+    object1.AddNewBehavior(project, "MyExtension::MyBehavior", "MyBehavior");
+    gd::Object &object2 =
+        layout.InsertNewObject(project, "MyExtension::Sprite", "MyObject2", 0);
+    // object2 doesn't have the behavior.
+
+    auto &group = layout.GetObjectGroups().InsertNew("MyGroup", 0);
+    group.AddObject(object1.GetName());
+    group.AddObject(object2.GetName());
+
+    REQUIRE(GetTypeOfBehaviorInObjectOrGroup(project, layout, "MyGroup",
+                                             "MyBehavior", true) == "");
+  }
+
+  SECTION("Give an empty type for a group with behaviors of same name but different types") {
+    gd::Platform platform;
+    gd::Project project;
+    SetupProjectWithDummyPlatform(project, platform);
+
+    gd::Layout &layout = project.InsertNewLayout("Scene", 0);
+    gd::Object &object1 =
+        layout.InsertNewObject(project, "MyExtension::Sprite", "MyObject1", 0);
+    object1.AddNewBehavior(project, "MyExtension::MyBehavior", "MyBehavior");
+    gd::Object &object2 =
+        layout.InsertNewObject(project, "MyExtension::Sprite", "MyObject2", 0);
+    object2.AddNewBehavior(project, "MyExtension::MyOtherBehavior",
+                           "MyBehavior");
+
+    auto &group = layout.GetObjectGroups().InsertNew("MyGroup", 0);
+    group.AddObject(object1.GetName());
+    group.AddObject(object2.GetName());
+
+    REQUIRE(GetTypeOfBehaviorInObjectOrGroup(project, layout, "MyGroup",
+                                             "MyBehavior", true) == "");
+  }
+
+  SECTION("Give an empty type for an empty group") {
+    gd::Platform platform;
+    gd::Project project;
+    SetupProjectWithDummyPlatform(project, platform);
+
+    gd::Layout &layout = project.InsertNewLayout("Scene", 0);
+    auto &group = layout.GetObjectGroups().InsertNew("MyGroup", 0);
+
+    REQUIRE(GetTypeOfBehaviorInObjectOrGroup(project, layout, "MyGroup",
+                                             "MyBehavior", true) == "");
+  }
+}
--- a/Core/tests/Object.cpp
+++ b/Core/tests/Object.cpp
@@ -0,0 +1,45 @@
+/*
+ * GDevelop Core
+ * Copyright 2008-2016 Florian Rival (Florian.Rival@gmail.com). All rights
+ * reserved. This project is released under the MIT License.
+ */
+/**
+ * @file Tests covering serialization to JSON.
+ */
+#include "GDCore/Project/Object.h"
+#include "DummyPlatform.h"
+#include "GDCore/CommonTools.h"
+#include "GDCore/Events/Builtin/StandardEvent.h"
+#include "GDCore/Events/Event.h"
+#include "GDCore/Events/EventsList.h"
+#include "GDCore/Events/Serialization.h"
+#include "GDCore/Extensions/Builtin/SpriteExtension/SpriteObject.h"
+#include "GDCore/Extensions/Platform.h"
+#include "GDCore/Project/CustomObjectConfiguration.h"
+#include "GDCore/Project/EventsFunctionsExtension.h"
+#include "GDCore/Project/Layout.h"
+#include "GDCore/Project/ObjectsContainer.h"
+#include "GDCore/Project/Project.h"
+#include "GDCore/Project/Variable.h"
+#include "GDCore/Serialization/Serializer.h"
+#include "GDCore/Tools/SystemStats.h"
+#include "GDCore/Tools/VersionWrapper.h"
+#include "catch.hpp"
+
+using namespace gd;
+
+TEST_CASE("Object", "[common]") {
+
+  SECTION("Create an object with default behaviors") {
+    gd::Platform platform;
+    gd::Project project;
+    SetupProjectWithDummyPlatform(project, platform);
+
+    gd::Layout &layout = project.InsertNewLayout("Scene", 0);
+    gd::Object &object = layout.InsertNewObject(
+        project, "MyExtension::FakeObjectWithDefaultBehavior", "MyObject", 0);
+
+    REQUIRE(object.HasBehaviorNamed("Effect"));
+    REQUIRE(object.GetBehavior("Effect").IsDefaultBehavior());
+  }
+}
--- a/Core/tests/ObjectSerialization.cpp
+++ b/Core/tests/ObjectSerialization.cpp
@@ -225,4 +225,41 @@ TEST_CASE("ObjectSerialization", "[common]") {
    auto clonedObject = object.Clone();
    CheckCustomObjectConfiguration(*(clonedObject.get()));
  }
+
+  SECTION("Exclude default behaviors from serialization") {
+    gd::Platform platform;
+    gd::Project project;
+    SetupProjectWithDummyPlatform(project, platform);
+
+    gd::Layout &layout = project.InsertNewLayout("Scene", 0);
+    gd::Object &object = layout.InsertNewObject(
+        project, "MyExtension::FakeObjectWithDefaultBehavior", "MyObject", 0);
+    REQUIRE(object.HasBehaviorNamed("Effect"));
+
+    object.AddNewBehavior(project, "MyExtension::MyBehavior", "MyBehavior");
+    REQUIRE(object.HasBehaviorNamed("MyBehavior"));
+
+    SerializerElement projectElement;
+    project.SerializeTo(projectElement);
+
+    // Check serialized behaviors.
+    auto &layoutsElement = projectElement.GetChild("layouts");
+    layoutsElement.ConsiderAsArrayOf("layout");
+    REQUIRE(layoutsElement.GetChildrenCount() == 1);
+    auto &layoutElement = layoutsElement.GetChild(0);
+
+    REQUIRE(layoutElement.GetStringAttribute("name") == "Scene");
+    REQUIRE(layoutElement.HasChild("objects"));
+
+    auto &objectsElement = layoutElement.GetChild("objects");
+    objectsElement.ConsiderAsArrayOf("object");
+    REQUIRE(objectsElement.GetChildrenCount() == 1);
+    auto &objectElement = objectsElement.GetChild(0);
+
+    auto &behaviorsElement = objectElement.GetChild("behaviors");
+    behaviorsElement.ConsiderAsArrayOf("behavior");
+    REQUIRE(behaviorsElement.GetChildrenCount() == 1);
+    auto &behaviorElement = behaviorsElement.GetChild(0);
+    REQUIRE(behaviorElement.GetStringAttribute("name") == "MyBehavior");
+  }
 }
--- a/Core/tests/ResourcesMergingHelper.cpp
+++ b/Core/tests/ResourcesMergingHelper.cpp
@@ -16,6 +16,7 @@
 #include "GDCore/Tools/SystemStats.h"
 #include "GDCore/Tools/VersionWrapper.h"
 #include "catch.hpp"
+#include "GDCore/IDE/ResourceExposer.h"

 class MockFileSystem : public gd::AbstractFileSystem {
 public:
@@ -75,7 +76,7 @@ TEST_CASE("ResourcesMergingHelper", "[common]") {
    project.GetResourcesManager().AddResource(
        "Image3", "subfolder/image3.png", "image");

-    project.ExposeResources(resourcesMerger);
+    gd::ResourceExposer::ExposeWholeProjectResources(project, resourcesMerger);

    auto resourcesFilenames =
        resourcesMerger.GetAllResourcesOldAndNewFilename();
@@ -101,7 +102,7 @@ TEST_CASE("ResourcesMergingHelper", "[common]") {
    project.GetResourcesManager().AddResource(
        "Image3", "subfolder/image3.png", "image");

-    project.ExposeResources(resourcesMerger);
+    gd::ResourceExposer::ExposeWholeProjectResources(project, resourcesMerger);

    auto resourcesFilenames =
        resourcesMerger.GetAllResourcesOldAndNewFilename();
--- a/Core/tests/ResourcesRenamer.cpp
+++ b/Core/tests/ResourcesRenamer.cpp
@@ -11,6 +11,7 @@
 #include "GDCore/CommonTools.h"
 #include "GDCore/Project/Project.h"
 #include "catch.hpp"
+#include "GDCore/IDE/ResourceExposer.h"

 TEST_CASE("ResourcesRenamer", "[common]") {
  SECTION("It renames resources that are exposed") {
@@ -34,7 +35,7 @@ TEST_CASE("ResourcesRenamer", "[common]") {
    project.GetPlatformSpecificAssets().Set(
        "android", "some-other-icon", "Resource2");

-    project.ExposeResources(resourcesRenamer);
+    gd::ResourceExposer::ExposeWholeProjectResources(project, resourcesRenamer);

    // Check that resources were renamed were used.
    REQUIRE(project.GetPlatformSpecificAssets().Get("android", "some-icon") ==
@@ -72,7 +73,7 @@ TEST_CASE("ResourcesRenamer", "[common]") {
    project.GetPlatformSpecificAssets().Set(
        "android", "some-other-icon", "Resource2");

-    project.ExposeResources(resourcesRenamer);
+    gd::ResourceExposer::ExposeWholeProjectResources(project, resourcesRenamer);

    // TODO: This should not be necessary, but for now not all resources support embeddeds,
    // so we must call it manually:
--- a/Core/tests/WholeProjectRefactorer.cpp
+++ b/Core/tests/WholeProjectRefactorer.cpp
@@ -3348,10 +3348,21 @@ const gd::Instruction &CreateActionWithLayerParameter(gd::Project &project,
  action.SetParameter(3, gd::Expression("\"My layer\""));
  return event.GetActions().Insert(action);
 }
+const gd::Instruction &CreateActionWithEmptyLayerParameter(gd::Project &project,
+                                                      gd::EventsList &events) {
+  gd::StandardEvent &event = dynamic_cast<gd::StandardEvent &>(
+      events.InsertNewEvent(project, "BuiltinCommonInstructions::Standard"));

+  gd::Instruction action;
+  action.SetType("MyExtension::SetCameraCenterX");
+  action.SetParametersCount(4);
+  action.SetParameter(3, gd::Expression(""));
+  return event.GetActions().Insert(action);
+}
 const gd::Instruction &
 CreateExpressionWithLayerParameter(gd::Project &project,
-                                   gd::EventsList &events) {
+                                   gd::EventsList &events,
+                                   const gd::String &layerName) {
  gd::StandardEvent &event = dynamic_cast<gd::StandardEvent &>(
      events.InsertNewEvent(project, "BuiltinCommonInstructions::Standard"));

@@ -3359,8 +3370,8 @@ CreateExpressionWithLayerParameter(gd::Project &project,
  action.SetType("MyExtension::DoSomething");
  action.SetParametersCount(1);
  action.SetParameter(
-      0, gd::Expression("MyExtension::CameraCenterX(\"My layer\") + "
-                        "MyExtension::CameraCenterX(\"My layer\")"));
+      0, gd::Expression("MyExtension::CameraCenterX(\"" + layerName + "\") + "
+                        "MyExtension::CameraCenterX(\"" + layerName + "\")"));
  return event.GetActions().Insert(action);
 }
 } // namespace
@@ -3390,13 +3401,13 @@ TEST_CASE("RenameLayer", "[common]") {
        project, otherExternalEvents.GetEvents());

    auto &layoutExpression =
-        CreateExpressionWithLayerParameter(project, layout.GetEvents());
+        CreateExpressionWithLayerParameter(project, layout.GetEvents(), "My layer");
    auto &externalExpression =
-        CreateExpressionWithLayerParameter(project, externalEvents.GetEvents());
+        CreateExpressionWithLayerParameter(project, externalEvents.GetEvents(), "My layer");
    auto &otherLayoutExpression =
-        CreateExpressionWithLayerParameter(project, otherLayout.GetEvents());
+        CreateExpressionWithLayerParameter(project, otherLayout.GetEvents(), "My layer");
    auto &otherExternalExpression = CreateExpressionWithLayerParameter(
-        project, otherExternalEvents.GetEvents());
+        project, otherExternalEvents.GetEvents(), "My layer");

    gd::WholeProjectRefactorer::RenameLayer(project, layout, "My layer",
                                            "My renamed layer");
@@ -3434,7 +3445,7 @@ TEST_CASE("RenameLayer", "[common]") {
    auto &layout = project.InsertNewLayout("My layout", 0);

    auto &layoutExpression =
-        CreateExpressionWithLayerParameter(project, layout.GetEvents());
+        CreateExpressionWithLayerParameter(project, layout.GetEvents(), "My layer");

    gd::WholeProjectRefactorer::RenameLayer(project, layout, "My layer",
                                            "layerA");
@@ -3443,6 +3454,57 @@ TEST_CASE("RenameLayer", "[common]") {
            "MyExtension::CameraCenterX(\"layerA\") + "
            "MyExtension::CameraCenterX(\"layerA\")");
  }
+
+  SECTION("Can rename a layer when a layer parameter is empty") {
+    gd::Project project;
+    gd::Platform platform;
+    SetupProjectWithDummyPlatform(project, platform);
+
+    auto &layout = project.InsertNewLayout("My layout", 0);
+
+    auto &layoutAction =
+        CreateActionWithEmptyLayerParameter(project, layout.GetEvents());
+
+    gd::WholeProjectRefactorer::RenameLayer(project, layout, "My layer",
+                                            "layerA");
+
+    REQUIRE(layoutAction.GetParameter(0).GetPlainString() == "");
+  }
+
+  SECTION("Can't rename a layer to an empty name") {
+    gd::Project project;
+    gd::Platform platform;
+    SetupProjectWithDummyPlatform(project, platform);
+
+    auto &layout = project.InsertNewLayout("My layout", 0);
+
+    auto &layoutExpression =
+        CreateExpressionWithLayerParameter(project, layout.GetEvents(), "My layer");
+
+    gd::WholeProjectRefactorer::RenameLayer(project, layout, "My layer",
+                                            "");
+
+    REQUIRE(layoutExpression.GetParameter(0).GetPlainString() ==
+            "MyExtension::CameraCenterX(\"My layer\") + "
+            "MyExtension::CameraCenterX(\"My layer\")");
+  }
+
+  SECTION("Can't rename a layer from an empty name") {
+    gd::Project project;
+    gd::Platform platform;
+    SetupProjectWithDummyPlatform(project, platform);
+
+    auto &layout = project.InsertNewLayout("My layout", 0);
+
+    auto &layoutExpression =
+        CreateExpressionWithLayerParameter(project, layout.GetEvents(), "");
+
+    gd::WholeProjectRefactorer::RenameLayer(project, layout, "", "My layer");
+
+    REQUIRE(layoutExpression.GetParameter(0).GetPlainString() ==
+            "MyExtension::CameraCenterX(\"\") + "
+            "MyExtension::CameraCenterX(\"\")");
+  }
 }

 namespace {
@@ -3625,7 +3687,6 @@ TEST_CASE("RenameLayerEffect", "[common]") {
    auto &wrongLayerExpression =
        CreateExpressionWithLayerEffectParameter(project, layout.GetEvents(), "My layer 2");

-    std::cout << "RenameLayerEffect" << std::endl;
    gd::WholeProjectRefactorer::RenameLayerEffect(project, layout, layer, "My effect",
                                            "My renamed effect");

@@ -3659,3 +3720,129 @@ TEST_CASE("RenameLayerEffect", "[common]") {
            "MyExtension::LayerEffectParameter(\"My layer 2\", \"My effect\")");
  }
 }
+
+TEST_CASE("RemoveLayer", "[common]") {
+  SECTION("Can remove instances in a layout and its associated external layouts") {
+    gd::Project project;
+    gd::Platform platform;
+    SetupProjectWithDummyPlatform(project, platform);
+
+    auto &layout = project.InsertNewLayout("My layout", 0);
+    auto &otherLayout = project.InsertNewLayout("My other layout", 1);
+
+    layout.InsertNewLayer("My layer", 0);
+    otherLayout.InsertNewLayer("My layer", 0);
+    
+    auto &externalLayout =
+        project.InsertNewExternalLayout("My external layout", 0);
+    auto &otherExternalLayout =
+        project.InsertNewExternalLayout("My other external layout", 0);
+    externalLayout.SetAssociatedLayout("My layout");
+    otherExternalLayout.SetAssociatedLayout("My other layout");
+
+    auto &initialInstances = layout.GetInitialInstances();
+    initialInstances.InsertNewInitialInstance().SetLayer("My layer");
+    initialInstances.InsertNewInitialInstance().SetLayer("My layer");
+    initialInstances.InsertNewInitialInstance().SetLayer("My layer");
+    initialInstances.InsertNewInitialInstance().SetLayer("");
+    initialInstances.InsertNewInitialInstance().SetLayer("");
+    
+    auto &externalInitialInstances = externalLayout.GetInitialInstances();
+    externalInitialInstances.InsertNewInitialInstance().SetLayer("My layer");
+    externalInitialInstances.InsertNewInitialInstance().SetLayer("My layer");
+    externalInitialInstances.InsertNewInitialInstance().SetLayer("");
+
+    auto &otherInitialInstances = otherLayout.GetInitialInstances();
+    otherInitialInstances.InsertNewInitialInstance().SetLayer("My layer");
+
+    auto &otherExternalInitialInstances = otherExternalLayout.GetInitialInstances();
+    otherExternalInitialInstances.InsertNewInitialInstance().SetLayer("My layer");
+
+    REQUIRE(initialInstances.GetInstancesCount() == 5);
+    REQUIRE(externalInitialInstances.GetInstancesCount() == 3);
+    REQUIRE(otherInitialInstances.GetInstancesCount() == 1);
+    REQUIRE(otherExternalInitialInstances.GetInstancesCount() == 1);
+
+    REQUIRE(initialInstances.GetLayerInstancesCount("My layer") == 3);
+    REQUIRE(externalInitialInstances.GetLayerInstancesCount("My layer") == 2);
+
+    gd::WholeProjectRefactorer::RemoveLayer(project, layout, "My layer");
+
+    REQUIRE(initialInstances.GetInstancesCount() == 2);
+    REQUIRE(externalInitialInstances.GetInstancesCount() == 1);
+    REQUIRE(otherInitialInstances.GetInstancesCount() == 1);
+    REQUIRE(otherExternalInitialInstances.GetInstancesCount() == 1);
+
+    REQUIRE(initialInstances.GetLayerInstancesCount("My layer") == 0);
+    REQUIRE(externalInitialInstances.GetLayerInstancesCount("My layer") == 0);
+  }
+}
+
+TEST_CASE("MergeLayers", "[common]") {
+  SECTION("Can merge instances from a layout into another layout (and their associated external layouts)") {
+    gd::Project project;
+    gd::Platform platform;
+    SetupProjectWithDummyPlatform(project, platform);
+
+    auto &layout = project.InsertNewLayout("My layout", 0);
+    auto &otherLayout = project.InsertNewLayout("My other layout", 1);
+
+    layout.InsertNewLayer("My layer", 0);
+    otherLayout.InsertNewLayer("My layer", 0);
+    
+    auto &externalLayout =
+        project.InsertNewExternalLayout("My external layout", 0);
+    auto &otherExternalLayout =
+        project.InsertNewExternalLayout("My other external layout", 0);
+    externalLayout.SetAssociatedLayout("My layout");
+    otherExternalLayout.SetAssociatedLayout("My other layout");
+
+    auto &initialInstances = layout.GetInitialInstances();
+    initialInstances.InsertNewInitialInstance().SetLayer("My layer");
+    initialInstances.InsertNewInitialInstance().SetLayer("My layer");
+    initialInstances.InsertNewInitialInstance().SetLayer("My layer");
+    initialInstances.InsertNewInitialInstance().SetLayer("");
+    initialInstances.InsertNewInitialInstance().SetLayer("");
+    initialInstances.InsertNewInitialInstance().SetLayer("My other layer");
+    
+    auto &externalInitialInstances = externalLayout.GetInitialInstances();
+    externalInitialInstances.InsertNewInitialInstance().SetLayer("My layer");
+    externalInitialInstances.InsertNewInitialInstance().SetLayer("My layer");
+    externalInitialInstances.InsertNewInitialInstance().SetLayer("");
+    externalInitialInstances.InsertNewInitialInstance().SetLayer("My other layer");
+
+    auto &otherInitialInstances = otherLayout.GetInitialInstances();
+    otherInitialInstances.InsertNewInitialInstance().SetLayer("My layer");
+
+    auto &otherExternalInitialInstances = otherExternalLayout.GetInitialInstances();
+    otherExternalInitialInstances.InsertNewInitialInstance().SetLayer("My layer");
+
+    REQUIRE(initialInstances.GetInstancesCount() == 6);
+    REQUIRE(externalInitialInstances.GetInstancesCount() == 4);
+    REQUIRE(otherInitialInstances.GetInstancesCount() == 1);
+    REQUIRE(otherExternalInitialInstances.GetInstancesCount() == 1);
+
+    REQUIRE(initialInstances.GetLayerInstancesCount("My layer") == 3);
+    REQUIRE(externalInitialInstances.GetLayerInstancesCount("My layer") == 2);
+
+    gd::WholeProjectRefactorer::MergeLayers(project, layout, "My layer", "");
+
+    // No instance was removed.
+    REQUIRE(initialInstances.GetInstancesCount() == 6);
+    REQUIRE(externalInitialInstances.GetInstancesCount() == 4);
+    REQUIRE(otherInitialInstances.GetInstancesCount() == 1);
+    REQUIRE(otherExternalInitialInstances.GetInstancesCount() == 1);
+
+    // No instance remain in "My layer".
+    REQUIRE(initialInstances.GetLayerInstancesCount("My layer") == 0);
+    REQUIRE(externalInitialInstances.GetLayerInstancesCount("My layer") == 0);
+
+    // Layers with the same name in other layouts are untouched.
+    REQUIRE(otherInitialInstances.GetLayerInstancesCount("My layer") == 1);
+    REQUIRE(otherExternalInitialInstances.GetLayerInstancesCount("My layer") == 1);
+
+    // Other layers from the same layout are untouched.
+    REQUIRE(initialInstances.GetLayerInstancesCount("My other layer") == 1);
+    REQUIRE(externalInitialInstances.GetLayerInstancesCount("My other layer") == 1);
+  }
+}
--- a/ExtLibs/CMakeLists.txt
+++ b/ExtLibs/CMakeLists.txt
@@ -0,0 +1 @@
+
--- a/Extensions/3D/A_RuntimeObject3D.ts
+++ b/Extensions/3D/A_RuntimeObject3D.ts
@@ -16,7 +16,13 @@ namespace gdjs {
  /**
   * Base class for 3D objects.
   */
-  export abstract class RuntimeObject3D extends gdjs.RuntimeObject {
+  export abstract class RuntimeObject3D
+    extends gdjs.RuntimeObject
+    implements
+      gdjs.Resizable,
+      gdjs.Scalable,
+      gdjs.Flippable,
+      gdjs.Base3DHandler {
    /**
     * Position on the Z axis.
     */
@@ -108,19 +114,8 @@ namespace gdjs {
        this.setWidth(initialInstanceData.width);
        this.setHeight(initialInstanceData.height);
      }
-      initialInstanceData.numberProperties.forEach((property) => {
-        if (property.name === 'z') {
-          this.setZ(property.value);
-        } else if (property.name === 'depth') {
-          if (initialInstanceData.customSize) {
-            this.setDepth(property.value);
-          }
-        } else if (property.name === 'rotationX') {
-          this.setRotationX(property.value);
-        } else if (property.name === 'rotationY') {
-          this.setRotationY(property.value);
-        }
-      });
+      if (initialInstanceData.depth !== undefined)
+        this.setDepth(initialInstanceData.depth);
    }

    setX(x: float): void {
@@ -268,6 +263,11 @@ namespace gdjs {
      this.invalidateHitboxes();
    }

+    setSize(newWidth: number, newHeight: number): void {
+      this.setWidth(newWidth);
+      this.setHeight(newHeight);
+    }
+
    /**
     * Set the object size on the Z axis (called "depth").
     */
--- a/Extensions/3D/AmbientLight.ts
+++ b/Extensions/3D/AmbientLight.ts
@@ -6,6 +6,9 @@ namespace gdjs {
        target: EffectsTarget,
        effectData: EffectData
      ): gdjs.PixiFiltersTools.Filter {
+        if (typeof THREE === 'undefined') {
+          return new gdjs.PixiFiltersTools.EmptyFilter();
+        }
        return new (class implements gdjs.PixiFiltersTools.Filter {
          light: THREE.AmbientLight;
          _isEnabled: boolean;
--- a/Extensions/3D/Base3DBehavior.ts
+++ b/Extensions/3D/Base3DBehavior.ts
@@ -0,0 +1,189 @@
+/*
+ * GDevelop JS Platform
+ * Copyright 2013-2023 Florian Rival (Florian.Rival@gmail.com). All rights reserved.
+ * This project is released under the MIT License.
+ */
+namespace gdjs {
+  export interface Base3DHandler {
+    /**
+     * Set the object position on the Z axis.
+     */
+    setZ(z: float): void;
+
+    /**
+     * Get the object position on the Z axis.
+     */
+    getZ(): float;
+
+    /**
+     * Set the object rotation on the X axis.
+     *
+     * This is an Euler angle. Objects use the `ZYX` order.
+     *
+     * @param angle the rotation angle on the X axis in degree
+     */
+    setRotationX(angle: float): void;
+
+    /**
+     * Set the object rotation on the Y axis.
+     *
+     * This is an Euler angle. Objects use the `ZYX` order.
+     *
+     * @param angle the rotation angle on the Y axis in degree
+     */
+    setRotationY(angle: float): void;
+
+    /**
+     * Get the object rotation on the X axis in degree.
+     *
+     * This is an Euler angle. Objects use the `ZYX` order.
+     */
+    getRotationX(): float;
+
+    /**
+     * Get the object rotation on the Y axis in degree.
+     *
+     * This is an Euler angle. Objects use the `ZYX` order.
+     */
+    getRotationY(): float;
+
+    /**
+     * Turn the object around the scene X axis at its center.
+     * @param deltaAngle the rotation angle in degree
+     */
+    turnAroundX(deltaAngle: float): void;
+
+    /**
+     * Turn the object around the scene Y axis at its center.
+     * @param deltaAngle the rotation angle in degree
+     */
+    turnAroundY(deltaAngle: float): void;
+
+    /**
+     * Turn the object around the scene Z axis at its center.
+     * @param deltaAngle the rotation angle in degree
+     */
+    turnAroundZ(deltaAngle: float): void;
+
+    /**
+     * Get the object size on the Z axis (called "depth").
+     */
+    getDepth(): float;
+
+    /**
+     * Set the object size on the Z axis (called "depth").
+     */
+    setDepth(depth: float): void;
+
+    /**
+     * Change the scale on Z axis of the object (changing its depth).
+     *
+     * @param newScale The new scale (must be greater than 0).
+     */
+    setScaleZ(newScale: number): void;
+
+    /**
+     * Get the scale of the object on Z axis.
+     *
+     * @return the scale of the object on Z axis
+     */
+    getScaleZ(): float;
+
+    flipZ(enable: boolean): void;
+
+    isFlippedZ(): boolean;
+  }
+
+  /**
+   * A behavior that forwards the Base3D interface to its object.
+   */
+  export class Base3DBehavior
+    extends gdjs.RuntimeBehavior
+    implements Base3DHandler {
+    private object: gdjs.RuntimeObject & Base3DHandler;
+
+    constructor(
+      instanceContainer: gdjs.RuntimeInstanceContainer,
+      behaviorData,
+      owner: gdjs.RuntimeObject & Base3DHandler
+    ) {
+      super(instanceContainer, behaviorData, owner);
+      this.object = owner;
+    }
+
+    updateFromBehaviorData(oldBehaviorData, newBehaviorData): boolean {
+      // Nothing to update.
+      return true;
+    }
+
+    onDeActivate() {}
+
+    onDestroy() {}
+
+    doStepPreEvents(instanceContainer: gdjs.RuntimeInstanceContainer) {}
+
+    doStepPostEvents(instanceContainer: gdjs.RuntimeInstanceContainer) {}
+
+    setZ(z: float): void {
+      this.object.setZ(z);
+    }
+
+    getZ(): float {
+      return this.object.getZ();
+    }
+
+    setRotationX(angle: float): void {
+      this.object.setRotationX(angle);
+    }
+
+    setRotationY(angle: float): void {
+      this.object.setRotationY(angle);
+    }
+
+    getRotationX(): float {
+      return this.object.getRotationX();
+    }
+
+    getRotationY(): float {
+      return this.object.getRotationY();
+    }
+
+    turnAroundX(deltaAngle: float): void {
+      this.object.turnAroundX(deltaAngle);
+    }
+
+    turnAroundY(deltaAngle: float): void {
+      this.object.turnAroundY(deltaAngle);
+    }
+
+    turnAroundZ(deltaAngle: float): void {
+      this.object.turnAroundZ(deltaAngle);
+    }
+
+    getDepth(): float {
+      return this.object.getDepth();
+    }
+
+    setDepth(depth: float): void {
+      this.object.setDepth(depth);
+    }
+
+    setScaleZ(newScale: number): void {
+      this.object.setScaleZ(newScale);
+    }
+
+    getScaleZ(): float {
+      return this.object.getScaleZ();
+    }
+
+    flipZ(enable: boolean): void {
+      this.object.flipZ(enable);
+    }
+
+    isFlippedZ(): boolean {
+      return this.object.isFlippedZ();
+    }
+  }
+
+  gdjs.registerBehavior('Scene3D::Base3DBehavior', gdjs.Base3DBehavior);
+}
--- a/Extensions/3D/CMakeLists.txt
+++ b/Extensions/3D/CMakeLists.txt
@@ -0,0 +1,23 @@
+cmake_minimum_required(VERSION 3.5)
+
+project(Scene3D)
+gd_add_extension_includes()
+
+# Defines
+#
+gd_add_extension_definitions(Scene3D)
+
+# The targets
+#
+include_directories(.)
+file(
+	GLOB
+	source_files
+	*.cpp
+	*.h)
+gd_add_clang_utils(Scene3D "${source_files}")
+gd_add_extension_target(Scene3D "${source_files}")
+
+# Linker files for the IDE extension
+#
+gd_extension_link_libraries(Scene3D)
--- a/Show More
+++ b/Show More