Fix cleaning

- This enforce slimits of 12 successful saves per minute globally and 6 per minute per
leaderboard. This is enough for the very large majority of games and avoid issues when sending too many scores because of a mistake or wrong game design.

Extensions/Leaderboards/leaderboardstools.ts

@@ -33,6 +33,49 @@ namespace gdjs {
         claimSecret?: string;
       };
 
+      // Rolling window rate limiting
+      // Implements rate limiting to prevent abuse:
+      // - Maximum 12 successful successful entries per minute across all leaderboards
+      // - Maximum 6 successful successful entries per minute per individual leaderboard
+      // - Works in addition to existing 500ms cooldown between entry tentatives
+      let _successfulEntriesGlobal: number[] = []; // Timestamps of successful entries across all leaderboards
+
+      const GLOBAL_RATE_LIMIT_COUNT = 12;
+      const PER_LEADERBOARD_RATE_LIMIT_COUNT = 6;
+      const RATE_LIMIT_WINDOW_MS = 60 * 1000; // 1 minute in milliseconds
+
+      /**
+       * Clean old entries from the rolling window (older than 1 minute)
+       */
+      const cleanOldEntries = (
+        entries: number[],
+        currentTime: number
+      ): number[] => {
+        return entries.filter(
+          (timestamp) => currentTime - timestamp < RATE_LIMIT_WINDOW_MS
+        );
+      };
+
+      /**
+       * Check if adding a new entry would exceed global rate limits.
+       */
+      const wouldExceedGlobalSuccessRateLimit = (): boolean => {
+        const currentTime = Date.now();
+        _successfulEntriesGlobal = cleanOldEntries(
+          _successfulEntriesGlobal,
+          currentTime
+        );
+        return _successfulEntriesGlobal.length >= GLOBAL_RATE_LIMIT_COUNT;
+      };
+
+      /**
+       * Record a successful entry for global rate limiting tracking.
+       */
+      const recordGlobalSuccessfulEntry = (): void => {
+        const currentTime = Date.now();
+        _successfulEntriesGlobal.push(currentTime);
+      };
+
       /**
        * Hold the state of the save of a score for a leaderboard.
        */
@@ -43,6 +86,9 @@ namespace gdjs {
         /** The promise that will be resolved when the score saving is done (successfully or not). */
         lastSavingPromise: Promise<void> | null = null;
 
+        /** Timestamps of successful entries for this leaderboard (for rate limiting) */
+        private _successfulEntries: number[] = [];
+
         // Score that is being saved:
         private _currentlySavingScore: number | null = null;
         private _currentlySavingPlayerName: string | null = null;
@@ -107,13 +153,36 @@ namespace gdjs {
           );
         }
 
-        private _isTooSoonToSaveAnotherScore(): boolean {
+        private _wouldExceedPerLeaderboardTentativeRateLimit(): boolean {
+          // Prevent entries within 500ms of each other (per leaderboard)
+          // as this would indicate surely a score saved every frame.
+          //
+          // Note that is on lastScoreSavingStartedAt, not lastScoreSavingSucceededAt,
+          // which means we limit tentatives here (and not successes).
           return (
             !!this.lastScoreSavingStartedAt &&
             Date.now() - this.lastScoreSavingStartedAt < 500
           );
         }
 
+        private _wouldExceedPerLeaderboardSuccessRateLimit(): boolean {
+          const currentTime = Date.now();
+          this._successfulEntries = cleanOldEntries(
+            this._successfulEntries,
+            currentTime
+          );
+          return (
+            this._successfulEntries.length >= PER_LEADERBOARD_RATE_LIMIT_COUNT
+          );
+        }
+
+        private _recordPerLeaderboardAndGlobalSuccessfulEntry(): void {
+          const currentTime = Date.now();
+          this._successfulEntries.push(currentTime);
+
+          recordGlobalSuccessfulEntry();
+        }
+
         startSaving({
           playerName,
           playerId,
@@ -141,7 +210,7 @@ namespace gdjs {
             throw new Error('Ignoring this saving request.');
           }
 
-          if (this._isTooSoonToSaveAnotherScore()) {
+          if (this._wouldExceedPerLeaderboardTentativeRateLimit()) {
             logger.warn(
               'Last entry was sent too little time ago. Ignoring this one.'
             );
@@ -154,6 +223,24 @@ namespace gdjs {
             throw new Error('Ignoring this saving request.');
           }
 
+          // Rolling window rate limiting check for successful entries.
+          if (wouldExceedGlobalSuccessRateLimit()) {
+            logger.warn(
+              'Rate limit exceeded. Too many entries have been successfully sent recently across all leaderboards. Ignoring this one.'
+            );
+            this._setError('GLOBAL_RATE_LIMIT_EXCEEDED');
+
+            throw new Error('Ignoring this saving request.');
+          }
+          if (this._wouldExceedPerLeaderboardSuccessRateLimit()) {
+            logger.warn(
+              'Rate limit exceeded. Too many entries have been successfully sent recently for this leaderboard. Ignoring this one.'
+            );
+            this._setError('LEADERBOARD_RATE_LIMIT_EXCEEDED');
+
+            throw new Error('Ignoring this saving request.');
+          }
+
           let resolveSavingPromise: () => void;
           const savingPromise = new Promise<void>((resolve) => {
             resolveSavingPromise = resolve;
@@ -169,6 +256,9 @@ namespace gdjs {
 
           return {
             closeSaving: (leaderboardEntry) => {
+              // Record successful entry for rolling window rate limiting.
+              this._recordPerLeaderboardAndGlobalSuccessfulEntry();
+
               if (savingPromise !== this.lastSavingPromise) {
                 logger.info(
                   'Score saving result received, but another save was launched in the meantime - ignoring the result of this one.'
@@ -396,7 +486,10 @@ namespace gdjs {
 
             try {
               const { closeSaving, closeSavingWithError } =
-                scoreSavingState.startSaving({ playerName, score });
+                scoreSavingState.startSaving({
+                  playerName,
+                  score,
+                });
 
               try {
                 const leaderboardEntry = await saveScore({
@@ -440,7 +533,10 @@ namespace gdjs {
 
             try {
               const { closeSaving, closeSavingWithError } =
-                scoreSavingState.startSaving({ playerId, score });
+                scoreSavingState.startSaving({
+                  playerId,
+                  score,
+                });
 
               try {
                 const leaderboardEntryId = await saveScore({

newIDE/app/.gitignore

@@ -1,5 +1,6 @@
 # Generated files
 src/Version/VersionMetadata.js
+public/service-worker.js
 
 # dependencies
 node_modules

newIDE/app/package-lock.json

@@ -33,7 +33,7 @@
         "path-browserify": "^1.0.1",
         "pixi-spine": "4.0.4",
         "pixi.js-legacy": "7.4.2",
-        "posthog-js": "^1.57.2",
+        "posthog-js": "1.275.2",
         "prop-types": "^15.5.10",
         "qr-creator": "^1.0.0",
         "react": "16.14.0",
@@ -5770,6 +5770,11 @@
         "url": "https://github.com/sponsors/sindresorhus"
       }
     },
+    "node_modules/@posthog/core": {
+      "version": "1.3.0",
+      "resolved": "https://registry.npmjs.org/@posthog/core/-/core-1.3.0.tgz",
+      "integrity": "sha512-hxLL8kZNHH098geedcxCz8y6xojkNYbmJEW+1vFXsmPcExyCXIUUJ/34X6xa9GcprKxd0Wsx3vfJQLQX4iVPhw=="
+    },
     "node_modules/@protobufjs/aspromise": {
       "version": "1.1.2",
       "license": "BSD-3-Clause"
@@ -25646,16 +25651,43 @@
       }
     },
     "node_modules/posthog-js": {
-      "version": "1.57.2",
-      "license": "MIT",
+      "version": "1.275.2",
+      "resolved": "https://registry.npmjs.org/posthog-js/-/posthog-js-1.275.2.tgz",
+      "integrity": "sha512-g1fnV/GAcEdwwk4EVbJ1HMZhlhgKYxG1Z5KPGvr+q5re0ltyVq8jFA2PsF333jvOlI8R01LLdpYSIgU8sBiZfg==",
       "dependencies": {
-        "fflate": "^0.4.1",
-        "rrweb-snapshot": "^1.1.14"
+        "@posthog/core": "1.3.0",
+        "core-js": "^3.38.1",
+        "fflate": "^0.4.8",
+        "preact": "^10.19.3",
+        "web-vitals": "^4.2.4"
+      },
+      "peerDependencies": {
+        "@rrweb/types": "2.0.0-alpha.17",
+        "rrweb-snapshot": "2.0.0-alpha.17"
+      },
+      "peerDependenciesMeta": {
+        "@rrweb/types": {
+          "optional": true
+        },
+        "rrweb-snapshot": {
+          "optional": true
+        }
+      }
+    },
+    "node_modules/posthog-js/node_modules/core-js": {
+      "version": "3.46.0",
+      "resolved": "https://registry.npmjs.org/core-js/-/core-js-3.46.0.tgz",
+      "integrity": "sha512-vDMm9B0xnqqZ8uSBpZ8sNtRtOdmfShrvT6h2TuQGLs0Is+cR0DYbj/KWP6ALVNbWPpqA/qPLoOuppJN07humpA==",
+      "hasInstallScript": true,
+      "funding": {
+        "type": "opencollective",
+        "url": "https://opencollective.com/core-js"
       }
     },
     "node_modules/preact": {
-      "version": "10.13.1",
-      "license": "MIT",
+      "version": "10.27.2",
+      "resolved": "https://registry.npmjs.org/preact/-/preact-10.27.2.tgz",
+      "integrity": "sha512-5SYSgFKSyhCbk6SrXyMpqjb5+MQBgfvEKE/OC+PujcY34sOpqtr+0AZQtPYx5IA6VxynQ7rUPCtKzyovpj9Bpg==",
       "funding": {
         "type": "opencollective",
         "url": "https://opencollective.com/preact"
@@ -30091,10 +30123,6 @@
         "node": ">= 10.13.0"
       }
     },
-    "node_modules/rrweb-snapshot": {
-      "version": "1.1.14",
-      "license": "MIT"
-    },
     "node_modules/rtl-css-js": {
       "version": "1.14.0",
       "license": "MIT",
@@ -33106,6 +33134,11 @@
         "defaults": "^1.0.3"
       }
     },
+    "node_modules/web-vitals": {
+      "version": "4.2.4",
+      "resolved": "https://registry.npmjs.org/web-vitals/-/web-vitals-4.2.4.tgz",
+      "integrity": "sha512-r4DIlprAGwJ7YM11VZp4R884m0Vmgr6EAKe3P+kO0PPj3Unqyvv59rczf6UiGcb9Z8QxZVcqKNwv/g0WNdWwsw=="
+    },
     "node_modules/webidl-conversions": {
       "version": "6.1.0",
       "dev": true,

newIDE/app/package.json

@@ -69,7 +69,7 @@
     "path-browserify": "^1.0.1",
     "pixi-spine": "4.0.4",
     "pixi.js-legacy": "7.4.2",
-    "posthog-js": "^1.57.2",
+    "posthog-js": "1.275.2",
     "prop-types": "^15.5.10",
     "qr-creator": "^1.0.0",
     "react": "16.14.0",

newIDE/app/scripts/make-service-worker.js

@@ -2,7 +2,7 @@ const fs = require('fs');
 const path = require('path');
 const shell = require('shelljs');
 const workboxBuild = require('workbox-build');
-const buildPath = '../build';
+const buildPath = '../public';
 const VersionMetadata = require('../src/Version/VersionMetadata');
 
 /**
@@ -46,7 +46,7 @@ const buildSW = () => {
   return workboxBuild
     .injectManifest({
       swSrc: 'service-worker-template/service-worker-template.js',
-      swDest: '../build/service-worker.js',
+      swDest: '../public/service-worker.js',
       globDirectory: buildPath,
       globPatterns: [
         // Application:
@@ -85,13 +85,13 @@ const buildSW = () => {
     .then(({ count, size, warnings }) => {
       if (
         !replaceInFile(
-          '../build/service-worker.js',
+          '../public/service-worker.js',
           'VersionMetadata = {}',
           'VersionMetadata = ' + JSON.stringify(VersionMetadata)
         )
       ) {
         console.error(
-          'Error while trying to replace version metadata in build/service-worker.js.'
+          'Error while trying to replace version metadata in public/service-worker.js.'
         );
         shell.exit(1);
       }

newIDE/app/scripts/service-worker-template/service-worker-template.js

@@ -1,64 +1,248 @@
-if (typeof importScripts === 'function') {
-  importScripts(
-    'https://storage.googleapis.com/workbox-cdn/releases/3.5.0/workbox-sw.js'
-  );
-  /* global workbox */
-  if (workbox) {
-    // Will be replaced by make-service-worker.js to include the proper version.
-    const VersionMetadata = {};
+/* eslint-disable no-restricted-globals */
 
-    // Contrary to other static assets (JS, CSS, HTML), libGD.js/wasm are not
-    // versioned in their filenames. Instead, we version using a query string
-    // (see src/index.js where it's loaded with the same query string).
-    workbox.precaching.precacheAndRoute([
-      {
-        url: `libGD.js?cache-buster=${VersionMetadata.versionWithHash}`,
-        revision: null, // Revision is null because versioning included in the URL.
-      },
-      {
-        url: `libGD.wasm?cache-buster=${VersionMetadata.versionWithHash}`,
-        revision: null, // Revision is null because versioning included in the URL.
-      },
-    ]);
+// ============================================================================
+// Browser Service Worker powered Preview ("Browser SW Preview"), using IndexedDB.
+// ============================================================================
 
-    /* injection point for manifest files.  */
-    workbox.precaching.precacheAndRoute([]);
+console.log('[ServiceWorker] Service worker file executed');
 
-    /* custom cache rules*/
-    workbox.routing.registerNavigationRoute('/index.html', {
-      blacklist: [/^\/_/, /\/[^\/]+\.[^\/]+$/],
-    });
+const swURL = new URL(self.location.href);
+const isDev = swURL.searchParams.has('dev');
 
-    // Cache resources from GDevelop cloudfront server (CORS enabled).
-    workbox.routing.registerRoute(
-      /https:\/\/resources\.gdevelop-app\.com\/.*$/,
-      workbox.strategies.networkFirst({
-        cacheName: 'gdevelop-resources-cache',
-        plugins: [
-          new workbox.expiration.Plugin({
-            maxEntries: 500,
-          }),
-        ],
-      })
-    );
+// If updated, also update the BrowserSWIndexedDB module.
+const DB_NAME = 'gdevelop-browser-sw-preview';
+const STORE_NAME = 'files';
+const DB_VERSION = 1;
 
-    // TODO: this should be useless?
-    workbox.routing.registerRoute(
-      /\.(?:png|gif|jpg|jpeg)$/,
-      workbox.strategies.networkFirst({
-        cacheName: 'images',
-        plugins: [
-          new workbox.expiration.Plugin({
-            maxEntries: 150,
-          }),
-        ],
-      })
-    );
-  } else {
-    console.log('Workbox could not be loaded - no offline support');
-  }
-} else {
-  console.log(
-    'importScripts does not exist on this browser - no offline support'
-  );
+/**
+ * Opens the IndexedDB database for browser SW preview files.
+ */
+function openBrowserSWPreviewDB() {
+  return new Promise((resolve, reject) => {
+    try {
+      const request = indexedDB.open(DB_NAME, DB_VERSION);
+
+      request.onerror = () => {
+        const error = request.error || new Error('Failed to open IndexedDB');
+        console.error('[ServiceWorker] Error opening preview database:', error);
+        reject(error);
+      };
+
+      request.onsuccess = () => {
+        const db = request.result;
+        resolve(db);
+      };
+
+      request.onupgradeneeded = () => {
+        console.log('[ServiceWorker] Upgrading preview database schema...');
+        const db = request.result;
+        if (!db.objectStoreNames.contains(STORE_NAME)) {
+          db.createObjectStore(STORE_NAME);
+          console.log('[ServiceWorker] Created object store:', STORE_NAME);
+        }
+      };
+    } catch (error) {
+      console.error('[ServiceWorker] Exception while opening preview database:', error);
+      reject(error);
+    }
+  });
+}
+
+/**
+ * Retrieves a preview file from IndexedDB.
+ */
+async function getBrowserSWPreviewFile(path) {
+  try {
+    const db = await openBrowserSWPreviewDB();
+
+    return new Promise((resolve, reject) => {
+      let settled = false;
+      const safeResolve = (v) => { if (!settled) { settled = true; resolve(v); } };
+      const safeReject  = (e) => { if (!settled) { settled = true; reject(e); } };
+
+      try {
+        // Sanity-check the store exists (avoids InvalidStateError).
+        if (!db.objectStoreNames.contains(STORE_NAME)) {
+          const err = new Error(`Object store "${STORE_NAME}" not found`);
+          console.error('[ServiceWorker] Missing object store while getting file:', path, err);
+          return safeReject(err);
+        }
+
+        const tx = db.transaction(STORE_NAME, 'readonly');
+
+        // If the transaction aborts (quota, deadlock, explicit abort, etc.), reject.
+        tx.onabort = () => {
+          const error = tx.error || new Error('Transaction aborted');
+          console.error('[ServiceWorker] Transaction aborted while getting file:', path, error);
+          safeReject(error);
+        };
+
+        // `onerror` at the transaction level can fire even if request handlers didn’t.
+        tx.onerror = () => {
+          const error = tx.error || new Error('Transaction failed');
+          console.error('[ServiceWorker] Transaction error while getting file:', path, error);
+          safeReject(error);
+        };
+
+        const store = tx.objectStore(STORE_NAME);
+        const req = store.get(path);
+
+        req.onsuccess = () => {
+          const result = req.result;
+          safeResolve(result || null);
+        };
+
+        req.onerror = () => {
+          const error = req.error || new Error('Get operation failed');
+          console.error('[ServiceWorker] Error retrieving file from IndexedDB:', path, error);
+          safeReject(error);
+        };
+      } catch (error) {
+        console.error('[ServiceWorker] Exception during get operation:', path, error);
+        safeReject(error);
+      }
+    });
+  } catch (error) {
+    console.error('[ServiceWorker] Failed to get file from IndexedDB:', path, error);
+    throw error;
+  }
+}
+
+/**
+ * Handles fetch events for browser SW preview files served from IndexedDB.
+ */
+self.addEventListener('fetch', (event) => {
+  const url = new URL(event.request.url);
+
+  // Check if this is a request for a browser SW preview file
+  if (url.pathname.startsWith('/browser_sw_preview/')) {
+    const relativePath = url.pathname.replace('/browser_sw_preview', '');
+
+    event.respondWith((async () => {
+      try {
+        // Try to get the file from IndexedDB
+        const fileRecord = await getBrowserSWPreviewFile(relativePath);
+
+        if (!fileRecord) {
+          console.warn('[ServiceWorker] File not found in IndexedDB:', relativePath);
+          return new Response('File not found in browser SW preview storage', {
+            status: 404,
+            headers: {
+              'Content-Type': 'text/plain',
+            }
+          });
+        }
+
+        // Return the file with appropriate headers
+        return new Response(fileRecord.bytes, {
+          status: 200,
+          headers: {
+            'Content-Type': fileRecord.contentType || 'application/octet-stream',
+            // Prevent caching to ensure latest version is always served
+            'Cache-Control': 'no-store, no-cache, must-revalidate',
+            'Pragma': 'no-cache',
+            'Expires': '0',
+            // CORS headers for cross-origin requests if needed
+            'Access-Control-Allow-Origin': '*',
+          }
+        });
+      } catch (error) {
+        console.error('[ServiceWorker] Error serving browser SW preview file:', relativePath, error);
+        return new Response('Error loading file from browser SW preview storage: ' + error.message, {
+          status: 500,
+          headers: {
+            'Content-Type': 'text/plain',
+          }
+        });
+      }
+    })());
+
+    // Return early to prevent falling through to workbox routes
+    return;
+  }
+});
+
+self.addEventListener('install', (event) => {
+  console.log('[ServiceWorker] Installing service worker...');
+  if (isDev) {
+    // In development, immediately use a new service worker.
+    self.skipWaiting();
+  }
+});
+
+self.addEventListener('activate', (event) => {
+  console.log('[ServiceWorker] Activating service worker...');
+
+  if (isDev) {
+    event.waitUntil(self.clients.claim());
+  }
+});
+
+// ============================================================================
+// Standard Workbox Configuration (for "semi-offline"/caching of GDevelop static files and resources)
+// ============================================================================
+
+self.__WB_DISABLE_DEV_LOGS = true;
+
+// eslint-disable-next-line no-undef
+importScripts(
+  'https://storage.googleapis.com/workbox-cdn/releases/3.5.0/workbox-sw.js'
+);
+
+/* global workbox */
+if (workbox) {
+  console.log('[ServiceWorker] Workbox loaded successfully');
+
+  // Will be replaced by make-service-worker.js to include the proper version.
+  const VersionMetadata = {};
+
+  // Contrary to other static assets (JS, CSS, HTML), libGD.js/wasm are not
+  // versioned in their filenames. Instead, we version using a query string
+  // (see src/index.js where it's loaded with the same query string).
+  workbox.precaching.precacheAndRoute([
+    {
+      url: `libGD.js?cache-buster=${VersionMetadata.versionWithHash}`,
+      revision: null, // Revision is null because versioning included in the URL.
+    },
+    {
+      url: `libGD.wasm?cache-buster=${VersionMetadata.versionWithHash}`,
+      revision: null, // Revision is null because versioning included in the URL.
+    },
+  ]);
+
+  /* injection point for manifest files.  */
+  workbox.precaching.precacheAndRoute([]);
+
+  /* custom cache rules*/
+  workbox.routing.registerNavigationRoute('/index.html', {
+    blacklist: [/^\/_/, /\/[^\/]+\.[^\/]+$/, /^\/browser_sw_preview\//],
+  });
+
+  // Cache resources from GDevelop cloudfront server (CORS enabled).
+  workbox.routing.registerRoute(
+    /https:\/\/resources\.gdevelop-app\.com\/.*$/,
+    workbox.strategies.networkFirst({
+      cacheName: 'gdevelop-resources-cache',
+      plugins: [
+        new workbox.expiration.Plugin({
+          maxEntries: 500,
+        }),
+      ],
+    })
+  );
+
+  // TODO: this should be useless?
+  workbox.routing.registerRoute(
+    /\.(?:png|gif|jpg|jpeg)$/,
+    workbox.strategies.networkFirst({
+      cacheName: 'images',
+      plugins: [
+        new workbox.expiration.Plugin({
+          maxEntries: 150,
+        }),
+      ],
+    })
+  );
+} else {
+  console.log('[ServiceWorker] Workbox could not be loaded - no offline support');
 }

newIDE/app/src/BrowserApp.js

@@ -9,6 +9,7 @@ import './UI/icomoon-font.css'; // Styles for Icomoon font.
 // Import for browser only IDE
 import browserResourceSources from './ResourcesList/BrowserResourceSources';
 import browserResourceExternalEditors from './ResourcesList/BrowserResourceExternalEditors';
+import BrowserSWPreviewLauncher from './ExportAndShare/BrowserExporters/BrowserSWPreviewLauncher';
 import BrowserS3PreviewLauncher from './ExportAndShare/BrowserExporters/BrowserS3PreviewLauncher';
 import {
   browserAutomatedExporters,
@@ -18,6 +19,7 @@ import {
 import makeExtensionsLoader from './JsExtensionsLoader/BrowserJsExtensionsLoader';
 import ObjectsEditorService from './ObjectEditor/ObjectsEditorService';
 import ObjectsRenderingService from './ObjectsRendering/ObjectsRenderingService';
+import { makeBrowserSWEventsFunctionCodeWriter } from './EventsFunctionsExtensionsLoader/CodeWriters/BrowserSWEventsFunctionCodeWriter';
 import { makeBrowserS3EventsFunctionCodeWriter } from './EventsFunctionsExtensionsLoader/CodeWriters/BrowserS3EventsFunctionCodeWriter';
 import Providers from './MainFrame/Providers';
 import ProjectStorageProviders from './ProjectsStorage/ProjectStorageProviders';
@@ -30,6 +32,7 @@ import BrowserResourceFetcher from './ProjectsStorage/ResourceFetcher/BrowserRes
 import BrowserEventsFunctionsExtensionOpener from './EventsFunctionsExtensionsLoader/Storage/BrowserEventsFunctionsExtensionOpener';
 import BrowserEventsFunctionsExtensionWriter from './EventsFunctionsExtensionsLoader/Storage/BrowserEventsFunctionsExtensionWriter';
 import BrowserLoginProvider from './LoginProvider/BrowserLoginProvider';
+import { isServiceWorkerSupported } from './ServiceWorkerSetup';
 
 export const create = (authentication: Authentication) => {
   Window.setUpContextMenu();
@@ -38,12 +41,17 @@ export const create = (authentication: Authentication) => {
 
   let app = null;
   const appArguments = Window.getArguments();
+  const canUseBrowserSW = isServiceWorkerSupported();
 
   app = (
     <Providers
       authentication={authentication}
       disableCheckForUpdates={!!appArguments['disable-update-check']}
-      makeEventsFunctionCodeWriter={makeBrowserS3EventsFunctionCodeWriter}
+      makeEventsFunctionCodeWriter={
+        canUseBrowserSW
+          ? makeBrowserSWEventsFunctionCodeWriter
+          : makeBrowserS3EventsFunctionCodeWriter
+      }
       eventsFunctionsExtensionWriter={BrowserEventsFunctionsExtensionWriter}
       eventsFunctionsExtensionOpener={BrowserEventsFunctionsExtensionOpener}
     >
@@ -67,9 +75,13 @@ export const create = (authentication: Authentication) => {
           }) => (
             <MainFrame
               i18n={i18n}
-              renderPreviewLauncher={(props, ref) => (
-                <BrowserS3PreviewLauncher {...props} ref={ref} />
-              )}
+              renderPreviewLauncher={(props, ref) =>
+                canUseBrowserSW ? (
+                  <BrowserSWPreviewLauncher {...props} ref={ref} />
+                ) : (
+                  <BrowserS3PreviewLauncher {...props} ref={ref} />
+                )
+              }
               renderShareDialog={props => (
                 <ShareDialog
                   project={props.project}
@@ -104,7 +116,9 @@ export const create = (authentication: Authentication) => {
                 filterExamples: !Window.isDev(),
               })}
               initialFileMetadataToOpen={initialFileMetadataToOpen}
-              initialExampleSlugToOpen={appArguments['create-from-example'] || null}
+              initialExampleSlugToOpen={
+                appArguments['create-from-example'] || null
+              }
             />
           )}
         </ProjectStorageProviders>

newIDE/app/src/EventsFunctionsExtensionsLoader/CodeWriters/BrowserSWEventsFunctionCodeWriter.js

@@ -0,0 +1,138 @@
+// @flow
+import {
+  type EventsFunctionCodeWriter,
+  type EventsFunctionCodeWriterCallbacks,
+} from '..';
+import {
+  deleteFilesWithPrefix,
+  putFile,
+  getBrowserSWPreviewBaseUrl,
+} from '../../ExportAndShare/BrowserExporters/BrowserSWPreviewLauncher/BrowserSWPreviewIndexedDB';
+import slugs from 'slugs';
+import debounce from 'lodash/debounce';
+
+let batchedWrites: Array<{
+  path: string,
+  content: string,
+  onSuccess: () => void,
+  onError: (error: Error) => void,
+}> = [];
+
+const flushBatchedWrites = debounce(async () => {
+  const writes = [...batchedWrites];
+  console.info(
+    `[BrowserSWEventsFunctionCodeWriter] Storing a batch of ${
+      writes.length
+    } extension generated files in IndexedDB...`
+  );
+
+  batchedWrites = [];
+
+  // Write all files to IndexedDB in parallel
+  const results = await Promise.allSettled(
+    writes.map(async write => {
+      const encoder = new TextEncoder();
+      const bytes = encoder.encode(write.content).buffer;
+      await putFile(write.path, bytes, 'text/javascript; charset=utf-8');
+      return write;
+    })
+  );
+
+  // Process results and call callbacks
+  results.forEach((result, index) => {
+    const write = writes[index];
+    if (result.status === 'fulfilled') {
+      write.onSuccess();
+    } else {
+      console.error(
+        `[BrowserSWEventsFunctionCodeWriter] Failed to store: ${write.path}`,
+        result.reason
+      );
+      write.onError(result.reason);
+    }
+  });
+}, 10); // Wait for up to 10ms, to avoid adding more latency to extension generation.
+
+/**
+ * Write a file by batching it with other files that are being written.
+ *
+ * Extension generated files are written in batches to avoid making a *lot* of IndexedDB transactions
+ * (games can have from dozens to **hundreds** of extensions and generated files).
+ */
+const writeFileInNextBatch = (path: string, content: string) => {
+  return new Promise((resolve, reject) => {
+    batchedWrites.push({
+      path,
+      content,
+      onSuccess: resolve,
+      onError: reject,
+    });
+    flushBatchedWrites();
+  });
+};
+
+/**
+ * Create the EventsFunctionCodeWriter that writes generated code for events functions
+ * to IndexedDB for service worker serving.
+ */
+export const makeBrowserSWEventsFunctionCodeWriter = ({
+  onWriteFile,
+}: EventsFunctionCodeWriterCallbacks): EventsFunctionCodeWriter => {
+  const baseUrl = getBrowserSWPreviewBaseUrl();
+  const extensionsCodeUrl = baseUrl + '/extensions-code';
+
+  // At startup, clean up the old generated files for extensions code.
+  (async () => {
+    try {
+      // TODO: This could break multiple tabs! Consider doing a folder per tab/session?
+      const relativePath = extensionsCodeUrl.replace(baseUrl, '');
+      await deleteFilesWithPrefix(relativePath + '/');
+    } catch (error) {
+      console.error(
+        `[BrowserSWEventsFunctionCodeWriter] Failed to clean generated files for extensions code in "${extensionsCodeUrl}/".`,
+        error
+      );
+    }
+  })();
+
+  const getPathFor = (codeNamespace: string) => {
+    return `${extensionsCodeUrl}/${slugs(codeNamespace)}.js`;
+  };
+
+  return {
+    getIncludeFileFor: (codeNamespace: string) => getPathFor(codeNamespace),
+
+    writeFunctionCode: (
+      functionCodeNamespace: string,
+      code: string
+    ): Promise<void> => {
+      const path = getPathFor(functionCodeNamespace);
+      onWriteFile({ includeFile: path, content: code });
+      const relativePath = path.replace(baseUrl, '');
+
+      return writeFileInNextBatch(relativePath, code);
+    },
+
+    writeBehaviorCode: (
+      behaviorCodeNamespace: string,
+      code: string
+    ): Promise<void> => {
+      const path = getPathFor(behaviorCodeNamespace);
+      onWriteFile({ includeFile: path, content: code });
+      const relativePath = path.replace(baseUrl, '');
+
+      return writeFileInNextBatch(relativePath, code);
+    },
+
+    writeObjectCode: (
+      objectCodeNamespace: string,
+      code: string
+    ): Promise<void> => {
+      const path = getPathFor(objectCodeNamespace);
+      onWriteFile({ includeFile: path, content: code });
+      const relativePath = path.replace(baseUrl, '');
+
+      return writeFileInNextBatch(relativePath, code);
+    },
+  };
+};

newIDE/app/src/ExportAndShare/BrowserExporters/BrowserFileSystem.js

@@ -38,10 +38,6 @@ const isURL = (filename: string) => {
 // Search for "pathPosix" in the codebase for other places where this is used.
 const pathPosix = path.posix || path;
 
-// TODO: Merge BrowserS3FileSystem into this? The way URLs are handled
-// is different though (BrowserS3FileSystem is not downloading anything
-// from URLs, while this file system does download files).
-
 /**
  * An in-memory "file system" that can be used for GDevelop exports.
  */

newIDE/app/src/ExportAndShare/BrowserExporters/BrowserPreview/BrowserPreviewDebuggerServer.js

@@ -59,19 +59,21 @@ const setupWindowClosedPolling = () => {
   }, 1000);
 };
 
-const PREVIEWS_ORIGIN = 'https://game-previews.gdevelop.io';
+let previewOrigin = null;
 
 /**
  * A debugger server implemented using the ability to send/receive messages
  * from popup windows in the browser.
  */
 export const browserPreviewDebuggerServer: PreviewDebuggerServer = {
-  startServer: async () => {
+  startServer: async ({ origin }) => {
     if (debuggerServerState === 'started') return;
     debuggerServerState = 'started';
 
+    previewOrigin = origin;
+
     window.addEventListener('message', event => {
-      if (event.origin !== PREVIEWS_ORIGIN) return;
+      if (event.origin !== previewOrigin) return;
 
       const id = getDebuggerIdForPreviewWindow(event.source);
       if (id === null) return; // Could not find the id of this preview window.
@@ -98,7 +100,7 @@ export const browserPreviewDebuggerServer: PreviewDebuggerServer = {
     if (!previewWindow) return;
 
     try {
-      previewWindow.postMessage(message, PREVIEWS_ORIGIN);
+      previewWindow.postMessage(message, previewOrigin);
     } catch (error) {
       console.error('Unable to send a message to the preview window:', error);
     }

newIDE/app/src/ExportAndShare/BrowserExporters/BrowserPreview/BrowserPreviewWindow.js

@@ -0,0 +1,34 @@
+// @flow
+import { displayBlackLoadingScreenOrThrow } from '../../../Utils/BrowserExternalWindowUtils';
+
+let nextPreviewWindowId = 0;
+
+/**
+ * Open a window showing a black "loading..." screen. It's important this is done
+ * NOT in an asynchronous way but JUST after a click. Otherwise, browsers like Safari
+ * will block the window opening.
+ */
+export const immediatelyOpenNewPreviewWindow = (
+  project: gdProject
+): WindowProxy => {
+  const width = project.getGameResolutionWidth();
+  const height = project.getGameResolutionHeight();
+  const left = window.screenX + window.innerWidth / 2 - width / 2;
+  const top = window.screenY + window.innerHeight / 2 - height / 2;
+
+  const targetId = 'GDevelopPreview' + nextPreviewWindowId++;
+  const previewWindow = window.open(
+    'about:blank',
+    targetId,
+    `width=${width},height=${height},left=${left},top=${top}`
+  );
+  if (!previewWindow) {
+    throw new Error(
+      "Can't open the preview window because of browser restrictions."
+    );
+  }
+
+  displayBlackLoadingScreenOrThrow(previewWindow);
+
+  return previewWindow;
+};

newIDE/app/src/ExportAndShare/BrowserExporters/BrowserS3PreviewLauncher/index.js

@@ -1,6 +1,6 @@
 // @flow
 import * as React from 'react';
-import BrowserPreviewErrorDialog from './BrowserPreviewErrorDialog';
+import BrowserPreviewErrorDialog from '../BrowserPreview/BrowserPreviewErrorDialog';
 import BrowserS3FileSystem from '../BrowserS3FileSystem';
 import { findGDJS } from '../../../GameEngineFinder/BrowserS3GDJSFinder';
 import assignIn from 'lodash/assignIn';
@@ -14,56 +14,23 @@ import {
   browserPreviewDebuggerServer,
   getExistingPreviewWindowForDebuggerId,
   registerNewPreviewWindow,
-} from './BrowserPreviewDebuggerServer';
+} from '../BrowserPreview/BrowserPreviewDebuggerServer';
 import Window from '../../../Utils/Window';
-import { displayBlackLoadingScreenOrThrow } from '../../../Utils/BrowserExternalWindowUtils';
 import { getGDevelopResourceJwtToken } from '../../../Utils/GDevelopServices/Project';
 import { isNativeMobileApp } from '../../../Utils/Platform';
 import { getIDEVersionWithHash } from '../../../Version';
+import { immediatelyOpenNewPreviewWindow } from '../BrowserPreview/BrowserPreviewWindow';
 const gd: libGDevelop = global.gd;
 
 type State = {|
   error: ?Error,
 |};
 
-let nextPreviewWindowId = 0;
-
-/**
- * Open a window showing a black "loading..." screen. It's important this is done
- * NOT in an asynchronous way but JUST after a click. Otherwise, browsers like Safari
- * will block the window opening.
- */
-export const immediatelyOpenNewPreviewWindow = (
-  project: gdProject
-): WindowProxy => {
-  const width = project.getGameResolutionWidth();
-  const height = project.getGameResolutionHeight();
-  const left = window.screenX + window.innerWidth / 2 - width / 2;
-  const top = window.screenY + window.innerHeight / 2 - height / 2;
-
-  const targetId = 'GDevelopPreview' + nextPreviewWindowId++;
-  const previewWindow = window.open(
-    'about:blank',
-    targetId,
-    `width=${width},height=${height},left=${left},top=${top}`
-  );
-  if (!previewWindow) {
-    throw new Error(
-      "Can't open the preview window because of browser restrictions."
-    );
-  }
-
-  displayBlackLoadingScreenOrThrow(previewWindow);
-
-  return previewWindow;
-};
-
 export default class BrowserS3PreviewLauncher extends React.Component<
   PreviewLauncherProps,
   State
 > {
   canDoNetworkPreview = () => false;
-  canDoHotReload = () => false;
 
   state = {
     error: null,
@@ -135,7 +102,9 @@ export default class BrowserS3PreviewLauncher extends React.Component<
         }).filter(Boolean);
 
     try {
-      await this.getPreviewDebuggerServer().startServer();
+      await this.getPreviewDebuggerServer().startServer({
+        origin: new URL(getBaseUrl()).origin,
+      });
     } catch (err) {
       // Ignore any error when running the debugger server - the preview
       // can still work without it.

newIDE/app/src/ExportAndShare/BrowserExporters/BrowserSWFileSystem.js

@@ -0,0 +1,246 @@
+// @flow
+import path from 'path-browserify';
+import {
+  deleteFilesWithPrefix,
+  putFile,
+} from './BrowserSWPreviewLauncher/BrowserSWPreviewIndexedDB';
+const gd: libGDevelop = global.gd;
+
+export type TextFileDescriptor = {|
+  filePath: string,
+  text: string,
+|};
+
+type ConstructorArgs = {|
+  filesContent: Array<TextFileDescriptor>,
+  baseUrl: string,
+|};
+
+const isURL = (filename: string) => {
+  return (
+    filename.startsWith('http://') ||
+    filename.startsWith('https://') ||
+    filename.startsWith('ftp://') ||
+    filename.startsWith('blob:') ||
+    filename.startsWith('data:')
+  );
+};
+
+/**
+ * Determines the content type based on file extension.
+ */
+const getContentType = (filePath: string): string => {
+  const ext = path.extname(filePath).toLowerCase();
+  const mimeTypes = {
+    '.html': 'text/html; charset=utf-8',
+    '.js': 'text/javascript; charset=utf-8',
+    '.mjs': 'text/javascript; charset=utf-8',
+    '.css': 'text/css; charset=utf-8',
+    '.json': 'application/json; charset=utf-8',
+    '.wasm': 'application/wasm',
+    '.png': 'image/png',
+    '.jpg': 'image/jpeg',
+    '.jpeg': 'image/jpeg',
+    '.gif': 'image/gif',
+    '.svg': 'image/svg+xml',
+    '.txt': 'text/plain; charset=utf-8',
+  };
+  return mimeTypes[ext] || 'application/octet-stream';
+};
+
+/**
+ * An in-memory "file system" that stores files in IndexedDB
+ * and serves them via a service worker for GDevelop previews.
+ */
+export default class BrowserSWFileSystem {
+  baseUrl: string;
+
+  // Store the content of some files.
+  _indexedFilesContent: { [string]: TextFileDescriptor };
+
+  // Store all the files that should be written to IndexedDB.
+  _pendingFiles: Array<{|
+    path: string,
+    content: string,
+    contentType: string,
+  |}> = [];
+
+  _pendingDeleteOperations: Array<Promise<any>> = [];
+
+  // Store a set of all external URLs copied so that we can simulate
+  // readDir result.
+  _allCopiedExternalUrls = new Set<string>();
+
+  constructor({ filesContent, baseUrl }: ConstructorArgs) {
+    this.baseUrl = baseUrl;
+
+    this._indexedFilesContent = {};
+    filesContent.forEach(textFileDescriptor => {
+      this._indexedFilesContent[
+        textFileDescriptor.filePath
+      ] = textFileDescriptor;
+    });
+  }
+
+  /**
+   * Uploads all pending files to IndexedDB.
+   */
+  applyPendingOperations = async () => {
+    try {
+      await Promise.all(this._pendingDeleteOperations);
+    } catch (error) {
+      console.error(
+        '[BrowserSWFileSystem] Error while deleting files in IndexedDB. Ignoring.',
+        error
+      );
+    }
+
+    try {
+      console.log(
+        `[BrowserSWFileSystem] Storing ${
+          this._pendingFiles.length
+        } files in IndexedDB for preview...`
+      );
+
+      let totalBytes = 0;
+      const uploadPromises = this._pendingFiles.map(async file => {
+        const fullPath = `/${file.path}`;
+        const encoder = new TextEncoder();
+        const bytes = encoder.encode(file.content).buffer;
+
+        totalBytes += bytes.byteLength;
+
+        await putFile(fullPath, bytes, file.contentType);
+      });
+
+      await Promise.all(uploadPromises);
+
+      console.log(
+        `[BrowserSWFileSystem] Successfully stored all ${
+          this._pendingFiles.length
+        } preview files in IndexedDB (${Math.ceil(totalBytes / 1000)} kB).`
+      );
+    } catch (error) {
+      console.error(
+        "[BrowserSWFileSystem] Can't store all files in IndexedDB:",
+        error
+      );
+      throw error;
+    }
+  };
+
+  mkDir = (path: string) => {
+    // Assume required directories always exist in a virtual file system.
+  };
+
+  dirExists = (path: string) => {
+    // Assume required directories always exist.
+    return true;
+  };
+
+  clearDir = (path: string) => {
+    console.info(`[BrowserSWFileSystem] Clearing directory: ${path}...`);
+    this._pendingDeleteOperations.push(deleteFilesWithPrefix(path));
+  };
+
+  getTempDir = () => {
+    return '/virtual-unused-tmp-dir';
+  };
+
+  fileNameFrom = (fullpath: string) => {
+    if (isURL(fullpath)) return fullpath;
+    return path.basename(fullpath);
+  };
+
+  dirNameFrom = (fullpath: string) => {
+    if (isURL(fullpath)) return '';
+    return path.dirname(fullpath);
+  };
+
+  makeAbsolute = (filename: string, baseDirectory: string) => {
+    if (isURL(filename)) return filename;
+
+    if (!this.isAbsolute(baseDirectory))
+      baseDirectory = path.resolve(baseDirectory);
+
+    return path.resolve(baseDirectory, path.normalize(filename));
+  };
+
+  makeRelative = (filename: string, baseDirectory: string) => {
+    if (isURL(filename)) return filename;
+    return path.relative(baseDirectory, path.normalize(filename));
+  };
+
+  isAbsolute = (fullpath: string) => {
+    if (isURL(fullpath)) return true;
+    if (fullpath.length === 0) return true;
+    return (
+      (fullpath.length > 0 && fullpath.charAt(0) === '/') ||
+      (fullpath.length > 1 && fullpath.charAt(1) === ':')
+    );
+  };
+
+  copyFile = (source: string, dest: string) => {
+    // URLs are not copied, just tracked.
+    if (isURL(source)) {
+      this._allCopiedExternalUrls.add(source);
+      return true;
+    }
+
+    console.warn(
+      '[BrowserSWFileSystem] Copy not done from',
+      source,
+      'to',
+      dest
+    );
+    return true;
+  };
+
+  writeToFile = (fullPath: string, contents: string) => {
+    // Remove the base URL to get the relative path
+    const relativePath = fullPath.replace(this.baseUrl, '');
+    const contentType = getContentType(fullPath);
+
+    // Queue the file to be written to IndexedDB
+    this._pendingFiles.push({
+      path: relativePath,
+      content: contents,
+      contentType,
+    });
+
+    return true;
+  };
+
+  readFile = (file: string) => {
+    if (!!this._indexedFilesContent[file])
+      return this._indexedFilesContent[file].text;
+
+    console.error(
+      `[BrowserSWFileSystem] Unknown file ${file}, returning an empty string`
+    );
+    return '';
+  };
+
+  readDir = (path: string, ext: string) => {
+    ext = ext.toUpperCase();
+    var output = new gd.VectorString();
+
+    // Simulate ReadDir by returning all external URLs
+    // with the filename matching the extension.
+    this._allCopiedExternalUrls.forEach(url => {
+      const upperCaseUrl = url.toUpperCase();
+      if (upperCaseUrl.indexOf(ext) === upperCaseUrl.length - ext.length) {
+        output.push_back(url);
+      }
+    });
+
+    return output;
+  };
+
+  fileExists = (filename: string) => {
+    if (isURL(filename)) return true;
+
+    // Assume all files asked for exist.
+    return true;
+  };
+}

newIDE/app/src/ExportAndShare/BrowserExporters/BrowserSWPreviewLauncher/BrowserSWPreviewIndexedDB.js

@@ -0,0 +1,240 @@
+// @flow
+
+// If updated, also update the service worker template.
+const DB_NAME = 'gdevelop-browser-sw-preview';
+const STORE_NAME = 'files';
+const DB_VERSION = 1;
+
+type FileRecord = {|
+  bytes: ArrayBuffer,
+  contentType: string,
+|};
+
+let dbInstance: ?IDBDatabase = null;
+
+/**
+ * Gets the base URL for browser service worker previews.
+ * This URL should be handled by the service worker to serve files from IndexedDB.
+ */
+export const getBrowserSWPreviewBaseUrl = (): string => {
+  // Use the current origin to ensure the service worker can intercept requests
+  const origin = window.location.origin;
+  return `${origin}/browser_sw_preview`;
+};
+
+/**
+ * Opens or returns the existing IndexedDB database connection.
+ * Handles database upgrades and version management.
+ */
+const openBrowserSWPreviewIndexedDB = (): Promise<IDBDatabase> => {
+  if (dbInstance && dbInstance.version === DB_VERSION) {
+    return Promise.resolve(dbInstance);
+  }
+
+  return new Promise((resolve, reject) => {
+    try {
+      // $FlowFixMe - indexedDB is available in all browsers
+      const request = indexedDB.open(DB_NAME, DB_VERSION);
+
+      request.onerror = () => {
+        const error = request.error || new Error('Failed to open IndexedDB');
+        console.error('[BrowserSWIndexedDB] Error opening database:', error);
+        reject(error);
+      };
+
+      request.onsuccess = () => {
+        dbInstance = request.result;
+        console.log('[BrowserSWIndexedDB] Database opened successfully');
+
+        // Handle unexpected close
+        dbInstance.onclose = () => {
+          console.warn(
+            '[BrowserSWIndexedDB] Database connection closed unexpectedly'
+          );
+          dbInstance = null;
+        };
+
+        // Handle version change (e.g., if another tab upgrades the DB)
+        dbInstance.onversionchange = () => {
+          console.warn(
+            '[BrowserSWIndexedDB] Database version changed, closing connection'
+          );
+          if (dbInstance) {
+            dbInstance.close();
+            dbInstance = null;
+          }
+        };
+
+        resolve(dbInstance);
+      };
+
+      request.onupgradeneeded = event => {
+        console.log('[BrowserSWIndexedDB] Upgrading database schema...');
+        const db = request.result;
+
+        // Create object store if it doesn't exist
+        if (!db.objectStoreNames.contains(STORE_NAME)) {
+          db.createObjectStore(STORE_NAME);
+          console.log('[BrowserSWIndexedDB] Created object store:', STORE_NAME);
+        }
+      };
+
+      request.onblocked = () => {
+        console.warn(
+          '[BrowserSWIndexedDB] Database upgrade blocked by another connection'
+        );
+        reject(
+          new Error(
+            'Database upgrade blocked. Please close other tabs using this application.'
+          )
+        );
+      };
+    } catch (error) {
+      console.error(
+        '[BrowserSWIndexedDB] Exception while opening database:',
+        error
+      );
+      reject(error);
+    }
+  });
+};
+
+/**
+ * Stores a "file" in IndexedDB.
+ */
+export const putFile = async (
+  path: string,
+  bytes: ArrayBuffer,
+  contentType: string
+): Promise<void> => {
+  try {
+    const db = await openBrowserSWPreviewIndexedDB();
+
+    return new Promise((resolve, reject) => {
+      try {
+        const transaction = db.transaction(STORE_NAME, 'readwrite');
+
+        transaction.onerror = () => {
+          const error = transaction.error || new Error('Transaction failed');
+          console.error(
+            '[BrowserSWIndexedDB] Transaction error while putting file:',
+            path,
+            error
+          );
+          reject(error);
+        };
+
+        transaction.onabort = () => {
+          const error = transaction.error || new Error('Transaction aborted');
+          console.error(
+            '[BrowserSWIndexedDB] Transaction aborted while putting file:',
+            path,
+            error
+          );
+          reject(error);
+        };
+
+        transaction.oncomplete = () => {
+          resolve();
+        };
+
+        const objectStore = transaction.objectStore(STORE_NAME);
+        const record: FileRecord = { bytes, contentType };
+
+        const request = objectStore.put(record, path);
+
+        request.onerror = () => {
+          const error = request.error || new Error('Put operation failed');
+          console.error(
+            '[BrowserSWIndexedDB] Error storing file:',
+            path,
+            error
+          );
+          reject(error);
+        };
+      } catch (error) {
+        console.error(
+          '[BrowserSWIndexedDB] Exception during put operation:',
+          path,
+          error
+        );
+        reject(error);
+      }
+    });
+  } catch (error) {
+    console.error('[BrowserSWIndexedDB] Failed to put file:', path, error);
+    throw error;
+  }
+};
+
+/**
+ * Deletes all "files" stored in IndexedDB with a given path prefix.
+ *
+ * @param pathPrefix - The path prefix to match.
+ */
+export const deleteFilesWithPrefix = async (
+  pathPrefix: string
+): Promise<number> => {
+  try {
+    const db = await openBrowserSWPreviewIndexedDB();
+
+    return new Promise((resolve, reject) => {
+      try {
+        const transaction = db.transaction(STORE_NAME, 'readwrite');
+        let deletedCount = 0;
+
+        transaction.onerror = () => {
+          const error = transaction.error || new Error('Transaction failed');
+          console.error(
+            '[BrowserSWIndexedDB] Transaction error while deleting files with prefix:',
+            pathPrefix,
+            error
+          );
+          reject(error);
+        };
+
+        transaction.oncomplete = () => {
+          resolve(deletedCount);
+        };
+
+        const objectStore = transaction.objectStore(STORE_NAME);
+        const request = objectStore.openCursor();
+
+        request.onsuccess = event => {
+          const cursor = event.target.result;
+          if (cursor) {
+            const key = cursor.key;
+            if (typeof key === 'string' && key.startsWith(pathPrefix)) {
+              cursor.delete();
+              deletedCount++;
+            }
+            cursor.continue();
+          }
+        };
+
+        request.onerror = () => {
+          const error = request.error || new Error('Cursor operation failed');
+          console.error(
+            '[BrowserSWIndexedDB] Error during cursor operation:',
+            error
+          );
+          reject(error);
+        };
+      } catch (error) {
+        console.error(
+          '[BrowserSWIndexedDB] Exception during delete with prefix:',
+          pathPrefix,
+          error
+        );
+        reject(error);
+      }
+    });
+  } catch (error) {
+    console.error(
+      '[BrowserSWIndexedDB] Failed to delete files with prefix:',
+      pathPrefix,
+      error
+    );
+    throw error;
+  }
+};

newIDE/app/src/ExportAndShare/BrowserExporters/BrowserSWPreviewLauncher/index.js

@@ -0,0 +1,281 @@
+// @flow
+import * as React from 'react';
+import BrowserPreviewErrorDialog from '../BrowserPreview/BrowserPreviewErrorDialog';
+import BrowserSWFileSystem from '../BrowserSWFileSystem';
+import { findGDJS } from '../../../GameEngineFinder/BrowserS3GDJSFinder';
+import assignIn from 'lodash/assignIn';
+import {
+  type PreviewOptions,
+  type PreviewLauncherProps,
+} from '../../PreviewLauncher.flow';
+import {
+  browserPreviewDebuggerServer,
+  registerNewPreviewWindow,
+} from '../BrowserPreview/BrowserPreviewDebuggerServer';
+import Window from '../../../Utils/Window';
+import { getGDevelopResourceJwtToken } from '../../../Utils/GDevelopServices/Project';
+import { isNativeMobileApp } from '../../../Utils/Platform';
+import { getIDEVersionWithHash } from '../../../Version';
+import { getBrowserSWPreviewBaseUrl } from './BrowserSWPreviewIndexedDB';
+import { immediatelyOpenNewPreviewWindow } from '../BrowserPreview/BrowserPreviewWindow';
+const gd: libGDevelop = global.gd;
+
+type State = {|
+  error: ?Error,
+|};
+
+export default class BrowserSWPreviewLauncher extends React.Component<
+  PreviewLauncherProps,
+  State
+> {
+  canDoNetworkPreview = () => false;
+
+  state = {
+    error: null,
+  };
+
+  _prepareExporter = (): Promise<{|
+    outputDir: string,
+    exporter: gdjsExporter,
+    browserSWFileSystem: BrowserSWFileSystem,
+  |}> => {
+    return findGDJS('preview').then(({ gdjsRoot, filesContent }) => {
+      console.info('[BrowserSWPreviewLauncher] GDJS found in', gdjsRoot);
+
+      const isForInGameEdition = false; // TODO: adapt for the 3D editor branch.
+
+      const baseUrl = getBrowserSWPreviewBaseUrl();
+      const outputDir = `${baseUrl}/${
+        isForInGameEdition ? 'in-game-editor-preview' : 'preview'
+      }`;
+
+      console.log(
+        '[BrowserSWPreviewLauncher] Preview will be served from:',
+        outputDir
+      );
+
+      const browserSWFileSystem = new BrowserSWFileSystem({
+        filesContent,
+        baseUrl: `${baseUrl}/`,
+      });
+      const fileSystem = assignIn(
+        new gd.AbstractFileSystemJS(),
+        browserSWFileSystem
+      );
+      const exporter = new gd.Exporter(fileSystem, gdjsRoot);
+      exporter.setCodeOutputDirectory(outputDir);
+
+      return {
+        exporter,
+        outputDir,
+        browserSWFileSystem,
+      };
+    });
+  };
+
+  launchPreview = async (previewOptions: PreviewOptions): Promise<any> => {
+    const { project, layout, externalLayout, numberOfWindows } = previewOptions;
+    this.setState({
+      error: null,
+    });
+
+    const debuggerIds = this.getPreviewDebuggerServer().getExistingDebuggerIds();
+    const shouldHotReload = previewOptions.hotReload && !!debuggerIds.length;
+
+    // Immediately open windows (otherwise Safari will block the window opening if done after
+    // an asynchronous operation).
+    const previewWindows = shouldHotReload
+      ? []
+      : Array.from({ length: numberOfWindows }, () => {
+          try {
+            return immediatelyOpenNewPreviewWindow(project);
+          } catch (error) {
+            console.error(
+              '[BrowserSWPreviewLauncher] Unable to open a new preview window - this window will be ignored:',
+              error
+            );
+            return null;
+          }
+        }).filter(Boolean);
+
+    try {
+      await this.getPreviewDebuggerServer().startServer({
+        origin: new URL(getBrowserSWPreviewBaseUrl()).origin,
+      });
+    } catch (err) {
+      // Ignore any error when running the debugger server - the preview
+      // can still work without it.
+      console.error(
+        '[BrowserSWPreviewLauncher] Unable to start the Debugger Server for the preview:',
+        err
+      );
+    }
+
+    try {
+      const {
+        exporter,
+        outputDir,
+        browserSWFileSystem,
+      } = await this._prepareExporter();
+
+      const previewExportOptions = new gd.PreviewExportOptions(
+        project,
+        outputDir
+      );
+      previewExportOptions.setLayoutName(layout.getName());
+      previewExportOptions.setIsDevelopmentEnvironment(Window.isDev());
+      if (externalLayout) {
+        previewExportOptions.setExternalLayoutName(externalLayout.getName());
+      }
+
+      previewExportOptions.useWindowMessageDebuggerClient();
+
+      const includeFileHashs = this.props.getIncludeFileHashs();
+      for (const includeFile in includeFileHashs) {
+        const hash = includeFileHashs[includeFile];
+        previewExportOptions.setIncludeFileHash(includeFile, hash);
+      }
+
+      previewExportOptions.setProjectDataOnlyExport(
+        // Only export project data if asked and if a hot-reloading is being done.
+        shouldHotReload && previewOptions.projectDataOnlyExport
+      );
+
+      previewExportOptions.setFullLoadingScreen(
+        previewOptions.fullLoadingScreen
+      );
+
+      previewExportOptions.setNativeMobileApp(isNativeMobileApp());
+      previewExportOptions.setGDevelopVersionWithHash(getIDEVersionWithHash());
+      previewExportOptions.setCrashReportUploadLevel(
+        this.props.crashReportUploadLevel
+      );
+      previewExportOptions.setPreviewContext(this.props.previewContext);
+      previewExportOptions.setProjectTemplateSlug(project.getTemplateSlug());
+      previewExportOptions.setSourceGameId(this.props.sourceGameId);
+
+      if (previewOptions.inAppTutorialMessageInPreview) {
+        previewExportOptions.setInAppTutorialMessageInPreview(
+          previewOptions.inAppTutorialMessageInPreview,
+          previewOptions.inAppTutorialMessagePositionInPreview
+        );
+      }
+
+      if (previewOptions.fallbackAuthor) {
+        previewExportOptions.setFallbackAuthor(
+          previewOptions.fallbackAuthor.id,
+          previewOptions.fallbackAuthor.username
+        );
+      }
+      if (previewOptions.authenticatedPlayer) {
+        previewExportOptions.setAuthenticatedPlayer(
+          previewOptions.authenticatedPlayer.playerId,
+          previewOptions.authenticatedPlayer.playerUsername,
+          previewOptions.authenticatedPlayer.playerToken
+        );
+      }
+      if (previewOptions.captureOptions.screenshots) {
+        previewOptions.captureOptions.screenshots.forEach(screenshot => {
+          previewExportOptions.addScreenshotCapture(
+            screenshot.delayTimeInSeconds,
+            screenshot.signedUrl,
+            screenshot.publicUrl
+          );
+        });
+      }
+
+      // The token, if any, to be used to read resources on GDevelop Cloud buckets.
+      const gdevelopResourceToken = getGDevelopResourceJwtToken();
+      if (gdevelopResourceToken)
+        previewExportOptions.setGDevelopResourceToken(gdevelopResourceToken);
+
+      console.log(
+        '[BrowserSWPreviewLauncher] Exporting project for preview...'
+      );
+      exporter.exportProjectForPixiPreview(previewExportOptions);
+      previewExportOptions.delete();
+      exporter.delete();
+
+      console.log(
+        '[BrowserSWPreviewLauncher] Storing preview files in IndexedDB...'
+      );
+      await browserSWFileSystem.applyPendingOperations();
+
+      if (shouldHotReload) {
+        console.log('[BrowserSWPreviewLauncher] Triggering hot reload...');
+        debuggerIds.forEach(debuggerId => {
+          this.getPreviewDebuggerServer().sendMessage(debuggerId, {
+            command: 'hotReload',
+          });
+        });
+      } else {
+        console.log(
+          '[BrowserSWPreviewLauncher] Opening new preview window(s)...'
+        );
+        previewWindows.forEach((previewWindow: WindowProxy) => {
+          // Change the HTML file displayed by the preview window so that it starts loading
+          // the game.
+          previewWindow.location = outputDir + '/index.html';
+          try {
+            previewWindow.focus();
+          } catch (e) {}
+
+          // Register the window so that it can be accessed
+          // by the debugger and for the captures to be detected when it closes.
+          const debuggerId = registerNewPreviewWindow(previewWindow);
+          browserPreviewDebuggerServer.registerCallbacks({
+            onErrorReceived: () => {},
+            onServerStateChanged: () => {},
+            onConnectionClosed: async ({ id }) => {
+              if (id !== debuggerId) {
+                return;
+              }
+
+              if (previewOptions.captureOptions) {
+                await this.props.onCaptureFinished(
+                  previewOptions.captureOptions
+                );
+              }
+            },
+            onConnectionOpened: () => {},
+            onConnectionErrored: () => {},
+            onHandleParsedMessage: () => {},
+          });
+        });
+      }
+
+      console.log('[BrowserSWPreviewLauncher] Preview launched successfully!');
+    } catch (error) {
+      console.error(
+        '[BrowserSWPreviewLauncher] Error launching preview:',
+        error
+      );
+      this.setState({
+        error,
+      });
+    }
+  };
+
+  getPreviewDebuggerServer() {
+    return browserPreviewDebuggerServer;
+  }
+
+  render() {
+    const { error } = this.state;
+
+    if (error) {
+      return (
+        <BrowserPreviewErrorDialog
+          error={error}
+          onClose={() =>
+            this.setState({
+              error: null,
+            })
+          }
+        />
+      );
+    }
+
+    return null;
+  }
+}

newIDE/app/src/ExportAndShare/LocalExporters/LocalPreviewLauncher/index.js

@@ -52,7 +52,6 @@ export default class LocalPreviewLauncher extends React.Component<
   State
 > {
   canDoNetworkPreview = () => true;
-  canDoHotReload = () => true;
 
   state = {
     networkPreviewDialogOpen: false,
@@ -204,7 +203,7 @@ export default class LocalPreviewLauncher extends React.Component<
     // useful if the user opens the Debugger editor later, or want to
     // hot reload.
     return this.getPreviewDebuggerServer()
-      .startServer()
+      .startServer({})
       .catch(err => {
         // Ignore any error when running the debugger server - the preview
         // can still work without it.

newIDE/app/src/ExportAndShare/PreviewLauncher.flow.js

@@ -91,7 +91,7 @@ export type ServerAddress = {
 
 /** Interface to run a debugger server for previews. */
 export type PreviewDebuggerServer = {|
-  startServer: () => Promise<void>,
+  startServer: ({ origin?: string }) => Promise<void>,
   getServerState: () => 'started' | 'stopped',
   getExistingDebuggerIds: () => Array<DebuggerId>,
   sendMessage: (id: DebuggerId, message: Object) => void,
@@ -112,7 +112,6 @@ export type HotReloaderLog = {|
 export type PreviewLauncherInterface = {
   launchPreview: (previewOptions: PreviewOptions) => Promise<any>,
   canDoNetworkPreview: () => boolean,
-  canDoHotReload: () => boolean,
   +closePreview?: (windowId: number) => void,
   +getPreviewDebuggerServer: () => ?PreviewDebuggerServer,
 };

newIDE/app/src/ServiceWorkerSetup.js

@@ -0,0 +1,73 @@
+// @flow
+import optionalRequire from './Utils/OptionalRequire';
+import { isNativeMobileApp } from './Utils/Platform';
+
+const PUBLIC_URL: string = process.env.PUBLIC_URL || '';
+const isDev = process.env.NODE_ENV !== 'production';
+
+const electron = optionalRequire('electron');
+const serviceWorker = navigator.serviceWorker;
+
+export function isServiceWorkerSupported() {
+  return !!serviceWorker;
+}
+
+export function registerServiceWorker() {
+  if (isNativeMobileApp() || !!electron) {
+    return;
+  }
+
+  if (!serviceWorker) {
+    console.warn(
+      'Service Worker not supported on this deployment (probably: not HTTPS and not localhost).'
+    );
+    return;
+  }
+
+  window.addEventListener('load', () => {
+    // Use a cache-buster for development so that the service worker is
+    // always reloaded when the app is reloaded.
+    const swUrl = isDev
+      ? `${PUBLIC_URL}/service-worker.js?dev=${Date.now()}`
+      : `${PUBLIC_URL}/service-worker.js`;
+
+    serviceWorker
+      .register(swUrl)
+      .then(registration => {
+        registration.onupdatefound = () => {
+          const installingWorker = registration.installing;
+          if (installingWorker == null) {
+            return;
+          }
+          installingWorker.onstatechange = () => {
+            if (installingWorker.state === 'installed') {
+              const alreadyHasAServiceWorker = !!serviceWorker.controller;
+              if (alreadyHasAServiceWorker) {
+                // At this point, the updated precached content has been fetched,
+                // but the previous service worker will still serve the older
+                // content until all client tabs are closed.
+                console.log(
+                  'New content is available and will be used when all tabs for this page are closed.'
+                );
+              } else {
+                // Service worker has been installed for the first time.
+                console.log('Content is cached for offline use.');
+              }
+            }
+          };
+        };
+      })
+      .catch(error => {
+        console.error('Error during service worker registration:', error);
+      });
+
+    if (isDev) {
+      serviceWorker.ready.then(registration => {
+        // Forces a check right now for a newer service worker script in development.
+        // If there is one, it will be installed (see the service worker script to verify how in development
+        // a new service worker script does a `self.skipWaiting()` and `self.clients.claim()`).
+        registration.update();
+      });
+    }
+  });
+}

newIDE/app/src/index.js

@@ -7,7 +7,7 @@ import {
   sendProgramOpening,
   installAnalyticsEvents,
 } from './Utils/Analytics/EventSender';
-import { register } from './serviceWorker';
+import { registerServiceWorker } from './ServiceWorkerSetup';
 import './UI/icomoon-font.css'; // Styles for Icomoon font.
 import optionalRequire from './Utils/OptionalRequire';
 import { loadScript } from './Utils/LoadScript';
@@ -168,5 +168,4 @@ if (rootElement) {
   ReactDOM.render(<Bootstrapper />, rootElement);
 } else console.error('No root element defined in index.html');
 
-// registerServiceWorker();
-register();
+registerServiceWorker();

newIDE/app/src/serviceWorker.js

@@ -1,150 +0,0 @@
-// This optional code is used to register a service worker.
-// register() is not called by default.
-
-// This lets the app load faster on subsequent visits in production, and gives
-// it offline capabilities. However, it also means that developers (and users)
-// will only see deployed updates on subsequent visits to a page, after all the
-// existing tabs open on the page have been closed, since previously cached
-// resources are updated in the background.
-
-// To learn more about the benefits of this model and instructions on how to
-// opt-in, read https://bit.ly/CRA-PWA
-
-const isLocalhost = Boolean(
-  window.location.hostname === 'localhost' ||
-    // [::1] is the IPv6 localhost address.
-    window.location.hostname === '[::1]' ||
-    // 127.0.0.0/8 are considered localhost for IPv4.
-    window.location.hostname.match(
-      /^127(?:\.(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)){3}$/
-    )
-);
-
-const PUBLIC_URL = process.env.PUBLIC_URL;
-
-export function register(config) {
-  if (process.env.NODE_ENV === 'production' && 'serviceWorker' in navigator) {
-    // The URL constructor is available in all browsers that support SW.
-    const publicUrl = new URL(PUBLIC_URL, window.location.href);
-    if (publicUrl.origin !== window.location.origin) {
-      // Our service worker won't work if PUBLIC_URL is on a different origin
-      // from what our page is served on. This might happen if a CDN is used to
-      // serve assets; see https://github.com/facebook/create-react-app/issues/2374
-      console.log(
-        `The origin in PUBLIC_URL (${
-          publicUrl.origin
-        }) is different than the current origin (${
-          window.location.origin
-        }) - Service Worker disabled`
-      );
-      return;
-    }
-
-    window.addEventListener('load', () => {
-      const swUrl = `${PUBLIC_URL}/service-worker.js`;
-
-      if (isLocalhost) {
-        // This is running on localhost. Let's check if a service worker still exists or not.
-        checkValidServiceWorker(swUrl, config);
-
-        // Add some additional logging to localhost, pointing developers to the
-        // service worker/PWA documentation.
-        navigator.serviceWorker.ready.then(() => {
-          console.log(
-            'This web app is being served cache-first by a service ' +
-              'worker. To learn more, visit https://bit.ly/CRA-PWA'
-          );
-        });
-      } else {
-        // Is not localhost. Just register service worker
-        registerValidSW(swUrl, config);
-      }
-    });
-  } else {
-    console.log(
-      'Development build (or unsupported browser) - Service Worker disabled'
-    );
-  }
-}
-
-function registerValidSW(swUrl, config) {
-  navigator.serviceWorker
-    .register(swUrl)
-    .then(registration => {
-      registration.onupdatefound = () => {
-        const installingWorker = registration.installing;
-        if (installingWorker == null) {
-          return;
-        }
-        installingWorker.onstatechange = () => {
-          if (installingWorker.state === 'installed') {
-            if (navigator.serviceWorker.controller) {
-              // At this point, the updated precached content has been fetched,
-              // but the previous service worker will still serve the older
-              // content until all client tabs are closed.
-              console.log(
-                'New content is available and will be used when all ' +
-                  'tabs for this page are closed. See https://bit.ly/CRA-PWA.'
-              );
-
-              // Execute callback
-              if (config && config.onUpdate) {
-                config.onUpdate(registration);
-              }
-            } else {
-              // At this point, everything has been precached.
-              // It's the perfect time to display a
-              // "Content is cached for offline use." message.
-              console.log('Content is cached for offline use.');
-
-              // Execute callback
-              if (config && config.onSuccess) {
-                config.onSuccess(registration);
-              }
-            }
-          }
-        };
-      };
-    })
-    .catch(error => {
-      console.error('Error during service worker registration:', error);
-    });
-}
-
-function checkValidServiceWorker(swUrl, config) {
-  // Check if the service worker can be found. If it can't reload the page.
-  fetch(swUrl, {
-    headers: { 'Service-Worker': 'script' },
-  })
-    .then(response => {
-      // Ensure service worker exists, and that we really are getting a JS file.
-      const contentType = response.headers.get('content-type');
-      if (
-        response.status === 404 ||
-        (contentType != null && contentType.indexOf('javascript') === -1)
-      ) {
-        // No service worker found. Probably a different app. Reload the page.
-        navigator.serviceWorker.ready.then(registration => {
-          registration.unregister().then(() => {
-            window.location.reload();
-          });
-        });
-      } else {
-        // Service worker found. Proceed as normal.
-        registerValidSW(swUrl, config);
-      }
-    })
-    .catch(() => {
-      console.log(
-        'No internet connection found. App is running in offline mode.'
-      );
-    });
-}
-
-export function unregister() {
-  if ('serviceWorker' in navigator) {
-    navigator.serviceWorker.ready.then(registration => {
-      registration.unregister();
-    });
-  }
-}

newIDE/app/src/stories/everything-else.stories.js

@@ -79,7 +79,7 @@ import EditorMosaicPlayground from './EditorMosaicPlayground';
 import EditorNavigator from '../UI/EditorMosaic/EditorNavigator';
 import PropertiesEditor from '../PropertiesEditor';
 import { OpenConfirmDialog } from '../ProjectsStorage/OpenConfirmDialog';
-import BrowserPreviewErrorDialog from '../ExportAndShare/BrowserExporters/BrowserS3PreviewLauncher/BrowserPreviewErrorDialog';
+import BrowserPreviewErrorDialog from '../ExportAndShare/BrowserExporters/BrowserPreview/BrowserPreviewErrorDialog';
 import RaisedButton from '../UI/RaisedButton';
 import Text from '../UI/Text';
 import IconButton from '../UI/IconButton';