diff --git a/newIDE/app/src/BehaviorsEditor/EnumerateBehaviorsMetadata.js b/newIDE/app/src/BehaviorsEditor/EnumerateBehaviorsMetadata.js
index f792c2a3e7..e125ad6386 100644
--- a/newIDE/app/src/BehaviorsEditor/EnumerateBehaviorsMetadata.js
+++ b/newIDE/app/src/BehaviorsEditor/EnumerateBehaviorsMetadata.js
@@ -43,3 +43,23 @@ export const enumerateBehaviorsMetadata = (
     })
   );
 };
+
+export const filterEnumeratedBehaviorMetadata = (
+  list: Array<EnumeratedBehaviorMetadata>,
+  searchText: string
+): Array<EnumeratedBehaviorMetadata> => {
+  if (!searchText) return list;
+
+  const lowercaseSearchText = searchText.toLowerCase();
+
+  return list.filter(enumerateBehaviorsMetadata => {
+    return (
+      enumerateBehaviorsMetadata.fullName
+        .toLowerCase()
+        .indexOf(lowercaseSearchText) !== -1 ||
+      enumerateBehaviorsMetadata.description
+        .toLowerCase()
+        .indexOf(lowercaseSearchText) !== -1
+    );
+  });
+};
diff --git a/newIDE/app/src/BehaviorsEditor/NewBehaviorDialog.js b/newIDE/app/src/BehaviorsEditor/NewBehaviorDialog.js
index c62b1540cb..d3fd79d1d9 100644
--- a/newIDE/app/src/BehaviorsEditor/NewBehaviorDialog.js
+++ b/newIDE/app/src/BehaviorsEditor/NewBehaviorDialog.js
@@ -9,6 +9,7 @@ import HelpButton from '../UI/HelpButton';
 import FlatButton from 'material-ui/FlatButton';
 import Subheader from 'material-ui/Subheader';
 import Avatar from 'material-ui/Avatar';
+import { Tabs, Tab } from 'material-ui/Tabs';
 import { List, ListItem } from 'material-ui/List';
 import Visibility from 'material-ui/svg-icons/action/visibility';
 import VisibilityOff from 'material-ui/svg-icons/action/visibility-off';
@@ -18,7 +19,11 @@ import { getDeprecatedBehaviorsInformation } from '../Hints';
 import {
   type EnumeratedBehaviorMetadata,
   enumerateBehaviorsMetadata,
+  filterEnumeratedBehaviorMetadata,
 } from './EnumerateBehaviorsMetadata';
+import SearchBar from 'material-ui-search-bar';
+import EmptyMessage from '../UI/EmptyMessage';
+import ExtensionsSearch from '../ExtensionsSearch';
 
 const styles = {
   icon: { borderRadius: 0 },
@@ -58,10 +63,22 @@ type Props = {|
 type State = {|
   behaviorMetadata: Array<EnumeratedBehaviorMetadata>,
   showDeprecated: boolean,
+  searchText: string,
 |};
 
 export default class NewBehaviorDialog extends Component<Props, State> {
-  state = { ...this._loadFrom(this.props.project), showDeprecated: false };
+  state = {
+    ...this._loadFrom(this.props.project),
+    showDeprecated: false,
+    searchText: '',
+  };
+  _searchBar = React.createRef<SearchBar>();
+
+  componentDidMount() {
+    setTimeout(() => {
+      if (this._searchBar.current) this._searchBar.current.focus();
+    }, 20 /* Be sure that the search bar is shown */);
+  }
 
   _loadFrom(
     project: gdProject
@@ -90,26 +107,29 @@ export default class NewBehaviorDialog extends Component<Props, State> {
     });
   };
 
+  _onNewExtensionInstalled = () => {
+    // Reload behaviors
+    this.setState(this._loadFrom(this.props.project));
+
+    // TODO: Go back to the first tab.
+    // TODO: Display snackbar?
+  };
+
   render() {
     const { project, open, onClose, objectType } = this.props;
-    const { showDeprecated, behaviorMetadata } = this.state;
+    const { showDeprecated, behaviorMetadata, searchText } = this.state;
     if (!open || !project) return null;
 
-    const actions = [
-      <FlatButton
-        key="close"
-        label={<Trans>Close</Trans>}
-        primary={false}
-        onClick={onClose}
-      />,
-    ];
-
     const deprecatedBehaviorsInformation = getDeprecatedBehaviorsInformation();
 
-    const behaviors = behaviorMetadata.filter(
+    const filteredBehaviorMetadata = filterEnumeratedBehaviorMetadata(
+      behaviorMetadata,
+      searchText
+    );
+    const behaviors = filteredBehaviorMetadata.filter(
       ({ type }) => !deprecatedBehaviorsInformation[type]
     );
-    const deprecatedBehaviors = behaviorMetadata.filter(
+    const deprecatedBehaviors = filteredBehaviorMetadata.filter(
       ({ type }) => !!deprecatedBehaviorsInformation[type]
     );
 
@@ -134,60 +154,106 @@ export default class NewBehaviorDialog extends Component<Props, State> {
       );
     };
 
+    const hasSearchNoResult =
+      !!searchText && !behaviors.length && !deprecatedBehaviors.length;
+
     return (
       <I18n>
         {({ i18n }) => (
           <Dialog
             title={<Trans>Add a new behavior to the object</Trans>}
-            actions={actions}
+            actions={[
+              <FlatButton
+                key="close"
+                label={<Trans>Close</Trans>}
+                primary={false}
+                onClick={onClose}
+              />,
+            ]}
             secondaryActions={<HelpButton helpPagePath="/behaviors" />}
             open={open}
             noMargin
             autoScrollBodyContent
           >
-            <List>
-              {behaviors.map((behaviorMetadata, index) => (
-                <BehaviorListItem
-                  key={index}
-                  behaviorMetadata={behaviorMetadata}
-                  onClick={() => chooseBehavior(i18n, behaviorMetadata)}
-                  disabled={!canBehaviorBeUsed(behaviorMetadata)}
+            <Tabs>
+              <Tab label={<Trans>Installed Behaviors</Trans>} value="installed">
+                <SearchBar
+                  value={searchText}
+                  onRequestSearch={() => {
+                    if (behaviors.length) {
+                      chooseBehavior(i18n, behaviors[0]);
+                    } else if (showDeprecated && deprecatedBehaviors.length) {
+                      chooseBehavior(i18n, deprecatedBehaviors[0]);
+                    }
+                  }}
+                  onChange={text =>
+                    this.setState({
+                      searchText: text,
+                    })
+                  }
+                  ref={this._searchBar}
                 />
-              ))}
-              {showDeprecated && (
-                <Subheader>
-                  Deprecated (old, prefer not to use anymore)
-                </Subheader>
-              )}
-              {showDeprecated &&
-                deprecatedBehaviors.map((behaviorMetadata, index) => (
-                  <BehaviorListItem
-                    key={index}
-                    behaviorMetadata={behaviorMetadata}
-                    onClick={() => chooseBehavior(i18n, behaviorMetadata)}
-                    disabled={!canBehaviorBeUsed(behaviorMetadata)}
-                  />
-                ))}
-            </List>
-            <Line justifyContent="center" alignItems="center">
-              {!showDeprecated ? (
-                <FlatButton
-                  key="toggle-experimental"
-                  icon={<Visibility />}
-                  primary={false}
-                  onClick={() => this._showDeprecated(true)}
-                  label={<Trans>Show deprecated (old) behaviors</Trans>}
+                {hasSearchNoResult && (
+                  <EmptyMessage>
+                    <Trans>
+                      No behavior found for your search. Try another search, or
+                      search for new behaviors to install.
+                    </Trans>
+                  </EmptyMessage>
+                )
+                // TODO: Button to search behaviors
+                }
+                <List>
+                  {behaviors.map((behaviorMetadata, index) => (
+                    <BehaviorListItem
+                      key={index}
+                      behaviorMetadata={behaviorMetadata}
+                      onClick={() => chooseBehavior(i18n, behaviorMetadata)}
+                      disabled={!canBehaviorBeUsed(behaviorMetadata)}
+                    />
+                  ))}
+                  {showDeprecated && !!deprecatedBehaviors.length && (
+                    <Subheader>
+                      Deprecated (old, prefer not to use anymore)
+                    </Subheader>
+                  )}
+                  {showDeprecated &&
+                    deprecatedBehaviors.map((behaviorMetadata, index) => (
+                      <BehaviorListItem
+                        key={index}
+                        behaviorMetadata={behaviorMetadata}
+                        onClick={() => chooseBehavior(i18n, behaviorMetadata)}
+                        disabled={!canBehaviorBeUsed(behaviorMetadata)}
+                      />
+                    ))}
+                </List>
+                <Line justifyContent="center" alignItems="center">
+                  {!showDeprecated ? (
+                    <FlatButton
+                      key="toggle-experimental"
+                      icon={<Visibility />}
+                      primary={false}
+                      onClick={() => this._showDeprecated(true)}
+                      label={<Trans>Show deprecated (old) behaviors</Trans>}
+                    />
+                  ) : (
+                    <FlatButton
+                      key="toggle-experimental"
+                      icon={<VisibilityOff />}
+                      primary={false}
+                      onClick={() => this._showDeprecated(false)}
+                      label={<Trans>Show deprecated (old) behaviors</Trans>}
+                    />
+                  )}
+                </Line>
+              </Tab>
+              <Tab label={<Trans>Search New Behaviors</Trans>} value="search">
+                <ExtensionsSearch
+                  project={project}
+                  onNewExtensionInstalled={this._onNewExtensionInstalled}
                 />
-              ) : (
-                <FlatButton
-                  key="toggle-experimental"
-                  icon={<VisibilityOff />}
-                  primary={false}
-                  onClick={() => this._showDeprecated(false)}
-                  label={<Trans>Show deprecated (old) behaviors</Trans>}
-                />
-              )}
-            </Line>
+              </Tab>
+            </Tabs>
           </Dialog>
         )}
       </I18n>
diff --git a/newIDE/app/src/ExtensionsSearch/ExtensionInstallDialog.js b/newIDE/app/src/ExtensionsSearch/ExtensionInstallDialog.js
new file mode 100644
index 0000000000..f91c78038a
--- /dev/null
+++ b/newIDE/app/src/ExtensionsSearch/ExtensionInstallDialog.js
@@ -0,0 +1,57 @@
+// @flow
+import { Trans } from '@lingui/macro';
+import React, { Component } from 'react';
+import Dialog from '../UI/Dialog';
+import FlatButton from 'material-ui/FlatButton';
+import { type ExtensionShortHeader } from '../Utils/GDevelopServices/Extension';
+import LeftLoader from '../UI/LeftLoader';
+
+type Props = {|
+  extensionShortHeader: ExtensionShortHeader,
+  isInstalling: boolean,
+  onClose: () => void,
+  onInstall: (type: string, defaultName: string) => void,
+|};
+type State = {||};
+
+export default class ExtensionInstallDialog extends Component<Props, State> {
+  // TODO: Load extension full header
+  render() {
+    const {
+      isInstalling,
+      extensionShortHeader,
+      onClose,
+      onInstall,
+    } = this.props;
+
+    return (
+      <Dialog
+        title={extensionShortHeader.fullName}
+        actions={[
+          <FlatButton
+            key="close"
+            label={<Trans>Back</Trans>}
+            primary={false}
+            onClick={onClose}
+            disabled={isInstalling}
+          />,
+          <LeftLoader isLoading={isInstalling}>
+            <FlatButton
+              key="install"
+              label={<Trans>Install in project</Trans>}
+              primary
+              onClick={onInstall}
+              disabled={isInstalling}
+            />
+          </LeftLoader>,
+        ]}
+        open
+        autoScrollBodyContent
+        onRequestClose={onClose}
+      >
+        {extensionShortHeader.shortDescription}
+        TODO: Display full description
+      </Dialog>
+    );
+  }
+}
diff --git a/newIDE/app/src/ExtensionsSearch/index.js b/newIDE/app/src/ExtensionsSearch/index.js
new file mode 100644
index 0000000000..e4159b064e
--- /dev/null
+++ b/newIDE/app/src/ExtensionsSearch/index.js
@@ -0,0 +1,201 @@
+// @flow
+import { t } from '@lingui/macro';
+import { Trans } from '@lingui/macro';
+import { I18n } from '@lingui/react';
+import { type I18n as I18nType } from '@lingui/core';
+
+import React, { Component } from 'react';
+import SearchBar from 'material-ui-search-bar';
+import {
+  getExtensionsRegistry,
+  type ExtensionsRegistry,
+  type ExtensionShortHeader,
+  type SerializedExtension,
+  getExtension,
+} from '../Utils/GDevelopServices/Extension';
+import { List, ListItem } from 'material-ui/List';
+import PlaceholderLoader from '../UI/PlaceholderLoader';
+import ExtensionInstallDialog from './ExtensionInstallDialog';
+import { unserializeFromJSObject } from '../Utils/Serializer';
+import { showErrorBox } from '../UI/Messages/MessageBox';
+
+type Props = {|
+  project: gdProject,
+  onNewExtensionInstalled: () => void,
+|};
+type State = {|
+  isInstalling: boolean,
+  selectedExtensionShortHeader: ?ExtensionShortHeader,
+  searchText: string,
+  extensionsRegistry: ?ExtensionsRegistry,
+|};
+
+// TODO: Factor this?
+const styles = {
+  icon: { width: 40, height: 40 },
+  disabledItem: { opacity: 0.6 },
+};
+
+const addSerializedExtensionToProject = (
+  project: gdProject,
+  serializedExtension: SerializedExtension
+) => {
+  const newEventsFunctionsExtension = project.insertNewEventsFunctionsExtension(
+    serializedExtension.name,
+    0
+  );
+
+  unserializeFromJSObject(
+    newEventsFunctionsExtension,
+    serializedExtension,
+    'unserializeFrom',
+    project
+  );
+  // TODO: Refresh project extensions
+};
+
+export default class ExtensionsSearch extends Component<Props, State> {
+  state = {
+    isInstalling: false,
+    extensionsRegistry: null,
+    selectedExtensionShortHeader: null,
+    searchText: '',
+  };
+  _searchBar = React.createRef<SearchBar>();
+
+  componentDidMount() {
+    getExtensionsRegistry().then(
+      extensionsRegistry => {
+        this.setState({
+          extensionsRegistry,
+        });
+      },
+      error => {
+        // handle error
+      }
+    );
+
+    // TODO: move this to componentDidUpdate
+    setTimeout(() => {
+      if (this._searchBar.current) this._searchBar.current.focus();
+    }, 20 /* Be sure that the search bar is shown */);
+  }
+
+  _install = (i18n: I18nType, extensionShortHeader: ExtensionShortHeader) => {
+    const { project } = this.props;
+
+    this.setState({
+      isInstalling: true,
+    });
+    getExtension(extensionShortHeader)
+      .then(
+        serializedExtension => {
+          addSerializedExtensionToProject(project, serializedExtension);
+          this.setState({
+            selectedExtensionShortHeader: null,
+          });
+          // TODO: Display newly added behaviors
+          // Use context to get functions to reload extensions.
+          this.props.onNewExtensionInstalled();
+        },
+        err => {
+          // handle error
+          showErrorBox(
+            i18n._(
+              t`Unable to load the extension. Verify that your internet connection is up, and try again later.`
+            ),
+            err
+          );
+        }
+      )
+      .then(() => {
+        this.setState({
+          isInstalling: false,
+        });
+      });
+  };
+
+  render() {
+    const { project } = this.props;
+    const {
+      selectedExtensionShortHeader,
+      extensionsRegistry,
+      searchText,
+      isInstalling,
+    } = this.state;
+
+    return (
+      <I18n>
+        {({ i18n }) => (
+          <React.Fragment>
+            <SearchBar
+              value={searchText}
+              onRequestSearch={() => {
+                //TODO: filtering
+              }}
+              onChange={searchText =>
+                this.setState({
+                  searchText,
+                })
+              }
+              ref={this._searchBar}
+            />
+            <List>
+              {!extensionsRegistry && <PlaceholderLoader />}
+              {!!extensionsRegistry &&
+                extensionsRegistry.extensionShortHeaders.map(
+                  extensionShortHeader => {
+                    const alreadyInstalled = project.hasEventsFunctionsExtensionNamed(
+                      extensionShortHeader.name
+                    );
+                    const disabled = alreadyInstalled;
+
+                    return (
+                      <ListItem
+                        key={extensionShortHeader.name}
+                        primaryText={
+                          <span>
+                            {extensionShortHeader.fullName}{' '}
+                            {alreadyInstalled && (
+                              <Trans> (already installed)</Trans>
+                            )}
+                          </span>
+                        }
+                        secondaryText={
+                          <p>{extensionShortHeader.shortDescription}</p>
+                        }
+                        secondaryTextLines={2}
+                        onClick={() =>
+                          this.setState({
+                            selectedExtensionShortHeader: extensionShortHeader,
+                          })
+                        }
+                        style={disabled ? styles.disabledItem : undefined}
+                        disabled={disabled}
+                      />
+                    );
+                  }
+                )
+              //TODO: Button to create a new extension
+              }
+            </List>
+            {!!selectedExtensionShortHeader && (
+              <ExtensionInstallDialog
+                isInstalling={isInstalling}
+                extensionShortHeader={selectedExtensionShortHeader}
+                onInstall={() =>
+                  this._install(i18n, selectedExtensionShortHeader)
+                }
+                onClose={() =>
+                  this.setState({
+                    selectedExtensionShortHeader: null,
+                  })
+                }
+              />
+            )}
+          </React.Fragment>
+        )}
+      </I18n>
+    );
+  }
+}
diff --git a/newIDE/app/src/MainFrame/index.js b/newIDE/app/src/MainFrame/index.js
index 44aae06d4f..c219910298 100644
--- a/newIDE/app/src/MainFrame/index.js
+++ b/newIDE/app/src/MainFrame/index.js
@@ -283,6 +283,7 @@ class MainFrame extends React.Component<Props, State> {
     });
   };
 
+  // TODO: Move this to a provider, take currentProject as parameter
   _loadProjectEventsFunctionsExtensions = () => {
     const { i18n } = this.props;
     if (this.props.eventsFunctionWriter && this.state.currentProject) {
diff --git a/newIDE/app/src/ProjectManager/index.js b/newIDE/app/src/ProjectManager/index.js
index 64dd7c272b..08e6620da0 100644
--- a/newIDE/app/src/ProjectManager/index.js
+++ b/newIDE/app/src/ProjectManager/index.js
@@ -501,6 +501,7 @@ export default class ProjectManager extends React.Component<Props, State> {
     newEventsFunctionsExtension.setName(newName);
 
     this.forceUpdate();
+    this.props.onReloadEventsFunctionsExtensions();
   };
 
   _moveUpEventsFunctionsExtension = (index: number) => {
diff --git a/newIDE/app/src/UI/LeftLoader.js b/newIDE/app/src/UI/LeftLoader.js
index 25428b8c43..86b1fa2da9 100644
--- a/newIDE/app/src/UI/LeftLoader.js
+++ b/newIDE/app/src/UI/LeftLoader.js
@@ -2,6 +2,10 @@
 import * as React from 'react';
 import CircularProgress from 'material-ui/CircularProgress';
 
+const styles = {
+  progress: { marginRight: 8, verticalAlign: 'middle' },
+};
+
 export default ({
   children,
   isLoading,
@@ -9,8 +13,8 @@ export default ({
   children: React.Node,
   isLoading: ?boolean,
 }) => (
-  <div style={{ display: 'flex', alignItems: 'center' }}>
-    {isLoading && <CircularProgress size={20} style={{ marginRight: 5 }} />}
+  <span>
+    {isLoading && <CircularProgress size={20} style={styles.progress} />}
     {children}
-  </div>
+  </span>
 );
diff --git a/newIDE/app/src/UI/RightLoader.js b/newIDE/app/src/UI/RightLoader.js
index 068eddd074..8d973daa71 100644
--- a/newIDE/app/src/UI/RightLoader.js
+++ b/newIDE/app/src/UI/RightLoader.js
@@ -2,6 +2,10 @@
 import * as React from 'react';
 import CircularProgress from 'material-ui/CircularProgress';
 
+const styles = {
+  progress: { marginLeft: 8, verticalAlign: 'middle' },
+};
+
 export default ({
   children,
   isLoading,
@@ -9,8 +13,8 @@ export default ({
   children: React.Node,
   isLoading: ?boolean,
 }) => (
-  <div style={{ display: 'flex', alignItems: 'center' }}>
+  <span>
     {children}
-    {isLoading && <CircularProgress size={20} style={{ marginLeft: 5 }} />}
-  </div>
+    {isLoading && <CircularProgress size={20} style={styles.progress} />}
+  </span>
 );
diff --git a/newIDE/app/src/Utils/GDevelopServices/ApiConfigs.js b/newIDE/app/src/Utils/GDevelopServices/ApiConfigs.js
index 3f58909bb0..18d049e87c 100644
--- a/newIDE/app/src/Utils/GDevelopServices/ApiConfigs.js
+++ b/newIDE/app/src/Utils/GDevelopServices/ApiConfigs.js
@@ -75,3 +75,9 @@ export const GDevelopReleaseApi = {
     ? 'https://c8cldf4iqh.execute-api.us-east-1.amazonaws.com/dev'
     : 'https://api.gdevelop-app.com/release',
 };
+
+export const GDevelopExtensionApi = {
+  baseUrl: isDev
+    ? 'https://raw.githubusercontent.com/4ian/GDevelop-extensions/master'
+    : 'https://raw.githubusercontent.com/4ian/GDevelop-extensions/master',
+};
diff --git a/newIDE/app/src/Utils/GDevelopServices/Extension.js b/newIDE/app/src/Utils/GDevelopServices/Extension.js
new file mode 100644
index 0000000000..e5a3032b12
--- /dev/null
+++ b/newIDE/app/src/Utils/GDevelopServices/Extension.js
@@ -0,0 +1,47 @@
+// @flow
+import axios from 'axios';
+import { GDevelopExtensionApi } from './ApiConfigs';
+
+export type ExtensionShortHeader = {|
+  shortDescription: string,
+  extensionNamespace: string,
+  fullName: string,
+  name: string,
+  version: string,
+  url: string,
+  headerUrl: string,
+|};
+export type ExtensionHeader = {|
+  ...ExtensionShortHeader,
+  description: string,
+|};
+
+export type SerializedExtension = {
+  ...ExtensionHeader,
+}
+
+export type ExtensionsRegistry = {
+  version: string,
+  extensionShortHeaders: Array<ExtensionShortHeader>,
+};
+
+export const getExtensionsRegistry = (): Promise<ExtensionsRegistry> => {
+  // TODO: Caching for a few minutes/hours?
+  return axios
+    .get(`${GDevelopExtensionApi.baseUrl}/extensions-registry.json`)
+    .then(response => response.data);
+};
+
+export const getExtensionHeader = (extensionShortHeader: ExtensionShortHeader): Promise<ExtensionHeader> => {
+  // TODO: Handle absolute urls?
+  return axios
+    .get(`${GDevelopExtensionApi.baseUrl}/${extensionShortHeader.headerUrl}`)
+    .then(response => response.data);
+};
+
+export const getExtension = (extensionHeader: ExtensionShortHeader | ExtensionHeader): Promise<SerializedExtension> => {
+  // TODO: Handle absolute urls?
+  return axios
+    .get(`${GDevelopExtensionApi.baseUrl}/${extensionHeader.url}`)
+    .then(response => response.data);
+};
diff --git a/newIDE/app/src/stories/index.js b/newIDE/app/src/stories/index.js
index 18a565a647..27dc2557b2 100644
--- a/newIDE/app/src/stories/index.js
+++ b/newIDE/app/src/stories/index.js
@@ -124,6 +124,7 @@ import EventsBasedBehaviorEditor from '../EventsBasedBehaviorEditor';
 import EventsBasedBehaviorEditorDialog from '../EventsBasedBehaviorEditor/EventsBasedBehaviorEditorDialog';
 import BehaviorTypeSelector from '../BehaviorTypeSelector';
 import ObjectTypeSelector from '../ObjectTypeSelector';
+import NewBehaviorDialog from '../BehaviorsEditor/NewBehaviorDialog';
 
 // No i18n in this file
 
@@ -2083,3 +2084,16 @@ storiesOf('ObjectTypeSelector', module)
       onChange={action('change')}
     />
   ));
+
+storiesOf('NewBehaviorDialog', module)
+  .addDecorator(muiDecorator)
+  .addDecorator(i18nProviderDecorator)
+  .add('default, for a Sprite object', () => (
+    <NewBehaviorDialog
+      open
+      project={project}
+      objectType={'Sprite'}
+      onClose={action('on close')}
+      onChoose={action('on choose')}
+    />
+  ));