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class="sidebar-filter-label" for="sidebar-filter-input"><span class="icon icon-filter"></span><span class="visually-hidden">Filter sidebar</span></label><input id="sidebar-filter-input" autoComplete="off" class="sidebar-filter-input-field false" type="text" placeholder="Filter" value=""/><button type="button" class="button action has-icon clear-sidebar-filter-button"><span class="button-wrap"><span class="icon icon-cancel "></span><span class="visually-hidden">Clear filter input</span></span></button></div></section></header><div class="sidebar-inner-nav"><div class="in-nav-toc"><div class="document-toc-container"><section class="document-toc"><header><h2 class="document-toc-heading">In this article</h2></header><ul class="document-toc-list"><li class="document-toc-item "><a class="document-toc-link" href="#key_resources">Key resources</a></li><li class="document-toc-item "><a class="document-toc-link" href="#get_started">Get started</a></li><li class="document-toc-item "><a class="document-toc-link" href="#concepts">Concepts</a></li><li class="document-toc-item "><a class="document-toc-link" href="#user_interface">User interface</a></li><li class="document-toc-item "><a class="document-toc-link" href="#how_to">How to</a></li><li class="document-toc-item "><a class="document-toc-link" href="#firefox_workflow_2">Firefox workflow</a></li><li class="document-toc-item "><a class="document-toc-link" href="#reference">Reference</a></li></ul></section></div></div><div class="sidebar-body"> <ol> <li class="section"><em><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions" aria-current="page">Browser extensions</a></em></li> <li> <details> <summary>Getting started</summary> <ol> <li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/What_are_WebExtensions">What are extensions?</a></li> <li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/Your_first_WebExtension">Your first extension</a></li> <li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/Your_second_WebExtension">Your second extension</a></li> <li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/Anatomy_of_a_WebExtension">Anatomy of an extension</a></li> <li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/Examples">Example extensions</a></li> <li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/What_next">What next?</a></li> </ol> </details> </li> <li> <details> <summary>Concepts</summary> <ol> <li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/API">JavaScript APIs</a></li> <li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/Content_scripts">Content scripts</a></li> <li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/Background_scripts">Background scripts</a></li> <li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/Match_patterns">Match patterns</a></li> <li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/Working_with_files">Work with files</a></li> <li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/Internationalization">Internationalization</a></li> <li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/Content_Security_Policy">Content Security Policy</a></li> <li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/Native_messaging">Native messaging</a></li> <li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/Differences_between_API_implementations">Differences between API implementations</a></li> <li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/Chrome_incompatibilities">Chrome incompatibilities</a></li> </ol> </details> </li> <li> <details> <summary>User interface</summary> <ol> <li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/user_interface">User interface</a></li> <li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/user_interface/Toolbar_button">Toolbar button</a></li> <li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/user_interface/Page_actions">Address bar button</a></li> <li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/user_interface/Sidebars">Sidebars</a></li> <li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/user_interface/Context_menu_items">Context menu items</a></li> <li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/user_interface/Options_pages">Options page</a></li> <li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/user_interface/Extension_pages">Extension pages</a></li> <li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/user_interface/Notifications">Notifications</a></li> <li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/user_interface/Omnibox">Address bar suggestions</a></li> <li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/user_interface/devtools_panels">devtools panels</a></li> </ol> </details> </li> <li> <details> <summary>How to</summary> <ol> <li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/Intercept_HTTP_requests">Intercept HTTP requests</a></li> <li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/Modify_a_web_page">Modify a web page</a></li> <li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/Safely_inserting_external_content_into_a_page">Insert external content</a></li> <li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/Sharing_objects_with_page_scripts">Share objects with page scripts</a></li> <li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/Add_a_button_to_the_toolbar">Add a button to the toolbar</a></li> <li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/Implement_a_settings_page">Implement a settings page</a></li> <li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/Working_with_the_Tabs_API">Work with the Tabs API</a></li> <li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/Work_with_the_Bookmarks_API">Work with the Bookmarks API</a></li> <li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/Work_with_the_Cookies_API">Work with the Cookies API</a></li> <li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/Work_with_contextual_identities">Work with contextual identities</a></li> <li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/Interact_with_the_clipboard">Interact with the clipboard</a></li> <li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/Extending_the_developer_tools">Extend the developer tools</a></li> <li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/Build_a_cross_browser_extension">Build a cross-browser extension</a></li> </ol> </details> </li> <li> <details> <summary>JavaScript APIs</summary> <ol><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/Browser_support_for_JavaScript_APIs">Browser support for JavaScript APIs</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/API/action">action</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/API/alarms">alarms</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/API/bookmarks">bookmarks</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/API/browserAction">browserAction</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/API/browserSettings">browserSettings</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/API/browsingData">browsingData</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/API/captivePortal">captivePortal</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/API/clipboard">clipboard</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/API/commands">commands</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/API/contentScripts">contentScripts</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/API/contextualIdentities">contextualIdentities</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/API/cookies">cookies</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/API/declarativeNetRequest">declarativeNetRequest</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/API/devtools">devtools</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/API/dns">dns</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/API/dom">dom</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/API/downloads">downloads</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/API/events">events</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/API/extension">extension</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/API/extensionTypes">extensionTypes</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/API/find">find</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/API/history">history</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/API/i18n">i18n</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/API/identity">identity</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/API/idle">idle</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/API/management">management</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/API/menus">menus</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/API/notifications">notifications</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/API/omnibox">omnibox</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/API/pageAction">pageAction</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/API/permissions">permissions</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/API/pkcs11">pkcs11</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/API/privacy">privacy</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/API/proxy">proxy</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/API/runtime">runtime</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/API/scripting">scripting</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/API/search">search</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/API/sessions">sessions</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/API/sidebarAction">sidebarAction</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/API/storage">storage</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/API/tabs">tabs</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/API/theme">theme</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/API/topSites">topSites</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/API/types">types</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/API/userScripts">userScripts</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/API/webNavigation">webNavigation</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/API/webRequest">webRequest</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/API/windows">windows</a></li></ol> </details> </li> <li> <details> <summary>Manifest keys</summary> <ol> <li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json">manifest.json</a></li> </ol> <ol><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json/action">action</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json/author">author</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json/background">background</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json/browser_action">browser_action</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json/browser_specific_settings">browser_specific_settings</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json/chrome_settings_overrides">chrome_settings_overrides</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json/chrome_url_overrides">chrome_url_overrides</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json/commands">commands</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json/content_scripts">content_scripts</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json/content_security_policy">content_security_policy</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json/declarative_net_request">declarative_net_request</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json/default_locale">default_locale</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json/description">description</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json/developer">developer</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json/devtools_page">devtools_page</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json/dictionaries">dictionaries</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json/externally_connectable">externally_connectable</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json/homepage_url">homepage_url</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json/host_permissions">host_permissions</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json/icons">icons</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json/incognito">incognito</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json/manifest_version">manifest_version</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json/name">name</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json/offline_enabled">offline_enabled</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json/omnibox">omnibox</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json/optional_host_permissions">optional_host_permissions</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json/optional_permissions">optional_permissions</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json/options_page">options_page</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json/options_ui">options_ui</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json/page_action">page_action</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json/permissions">permissions</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json/protocol_handlers">protocol_handlers</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json/short_name">short_name</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json/sidebar_action">sidebar_action</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json/storage">storage</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json/theme">theme</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json/theme_experiment">theme_experiment</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json/user_scripts">user_scripts</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json/version">version</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json/version_name">version_name</a></li><li><a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json/web_accessible_resources">web_accessible_resources</a></li></ol> </details> </li> <li> <details> <summary>Extension Workshop</summary> <ol> <li><a href="https://extensionworkshop.com/documentation/develop/">Develop</a></li> <li><a href="https://extensionworkshop.com/documentation/publish/">Publish</a></li> <li><a href="https://extensionworkshop.com/documentation/manage/">Manage</a></li> <li><a href="https://extensionworkshop.com/documentation/enterprise/">Enterprise</a></li> </ol> </details> </li> <li class="section"><a href="/en-US/docs/Mozilla/Add-ons/Contact_us">Contact us</a></li> <li> <details> <summary>Channels</summary> <ol> <li><a href="https://blog.mozilla.org/addons">Add-ons blog</a></li> <li><a href="https://discourse.mozilla.org/c/add-ons">Add-ons forum</a></li> <li><a href="https://chat.mozilla.org/#/room/%23addons:mozilla.org">Add-ons chat</a></li> </ol> </details> </li> </ol> </div></div><section class="place side"></section></nav></aside><div class="toc-container"><aside class="toc"><nav><div class="document-toc-container"><section class="document-toc"><header><h2 class="document-toc-heading">In this article</h2></header><ul class="document-toc-list"><li class="document-toc-item "><a class="document-toc-link" href="#key_resources">Key resources</a></li><li class="document-toc-item "><a class="document-toc-link" href="#get_started">Get started</a></li><li class="document-toc-item "><a class="document-toc-link" href="#concepts">Concepts</a></li><li class="document-toc-item "><a class="document-toc-link" href="#user_interface">User interface</a></li><li class="document-toc-item "><a class="document-toc-link" href="#how_to">How to</a></li><li class="document-toc-item "><a class="document-toc-link" href="#firefox_workflow_2">Firefox workflow</a></li><li class="document-toc-item "><a class="document-toc-link" href="#reference">Reference</a></li></ul></section></div></nav></aside><section class="place side"></section></div></div><main id="content" class="main-content "><article class="main-page-content" lang="en-US"><header><h1>Browser extensions</h1></header><div class="section-content"><p>Extensions, or add-ons, can modify and enhance the capability of a browser. Extensions for Firefox are built using the WebExtensions API cross-browser technology.</p> <p>The technology for extensions in Firefox is, to a large extent, compatible with the <a href="https://developer.chrome.com/docs/extensions/reference/" class="external" target="_blank">extension API</a> supported by Chromium-based browsers (such as Google Chrome, Microsoft Edge, Opera, Vivaldi). In most cases, extensions written for Chromium-based browsers run in Firefox with <a href="https://extensionworkshop.com/documentation/develop/porting-a-google-chrome-extension/" class="external" target="_blank">just a few changes</a>.</p></div><section aria-labelledby="key_resources"><h2 id="key_resources"><a href="#key_resources">Key resources</a></h2><div class="section-content"><dl> <dt id="guides"><a href="#guides">Guides</a></dt> <dd> <p>Whether you're just beginning or looking for more advanced advice, learn about how extensions work and use the WebExtensions API from our extensive range of <a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/What_are_WebExtensions">tutorials and guides</a>.</p> </dd> <dt id="references"><a href="#references">References</a></dt> <dd> <p>Get comprehensive details about the methods, properties, types, and events of the <a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/Browser_support_for_JavaScript_APIs">WebExtensions APIs</a> and full details about the <a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json">manifest keys</a>.</p> </dd> <dt id="firefox_workflow"><a href="#firefox_workflow">Firefox workflow</a></dt> <dd> <p>Discover how to build and publish extensions for Firefox: get the lowdown on developer tools, publication and distribution, and porting on <a href="https://extensionworkshop.com/" class="external" target="_blank">Extension Workshop</a>.</p> </dd> </dl> <div class="notecard note"> <p><strong>Note:</strong> If you have ideas or questions or need help, you can reach us on the <a href="https://discourse.mozilla.org/c/add-ons/35" class="external" target="_blank">community forum</a> or in the <a href="https://matrix.to/#/!CuzZVoCbeoDHsxMCVJ:mozilla.org?via=mozilla.org&via=matrix.org&via=humanoids.be" class="external" target="_blank">Add-ons Room</a> on <a href="https://wiki.mozilla.org/Matrix" class="external" target="_blank">Matrix</a>.</p> </div></div></section><section aria-labelledby="get_started"><h2 id="get_started"><a href="#get_started">Get started</a></h2><div class="section-content"><p>Discover <a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/What_are_WebExtensions">what extensions can do</a> before building <a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/Your_first_WebExtension">your first extension.</a> Learn about the <a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/Anatomy_of_a_WebExtension">anatomy of an extension</a> and get an overview of the <a href="https://extensionworkshop.com/documentation/develop/firefox-workflow-overview/" class="external" target="_blank">extension development and publication workflow, Firefox style</a>. Explore a little deeper with a comprehensive selection of <a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/Examples">example extensions</a> that you can run right in Firefox.</p></div></section><section aria-labelledby="concepts"><h2 id="concepts"><a href="#concepts">Concepts</a></h2><div class="section-content"><p>Get detailed information on the concept that underpin extensions <a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/API">from an overview of the JavaScript API</a>, through <a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/Content_scripts">content scripts,</a> <a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/Match_patterns">match patterns</a>, <a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/Working_with_files">working with files</a>, <a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/Internationalization">internationalization</a>, and <a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/Content_Security_Policy">content security policy</a>, to more advanced subjects such as <a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/Native_messaging">native messaging</a>, <a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/Extending_the_developer_tools">using the devtools APIs</a>, and <a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/Native_manifests">native manifests</a>.</p></div></section><section aria-labelledby="user_interface"><h2 id="user_interface"><a href="#user_interface">User interface</a></h2><div class="section-content"><p>Discover all the <a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/user_interface">user interface</a> components you can use in your extensions, with coding examples and tips.</p></div></section><section aria-labelledby="how_to"><h2 id="how_to"><a href="#how_to">How to</a></h2><div class="section-content"><p>From patterns you'll regularly use such as <a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/Working_with_the_Tabs_API">work with the Tabs API</a> and <a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/Add_a_button_to_the_toolbar">adding a button to the toolbar</a> to more advanced topics such as <a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/Intercept_HTTP_requests">intercepting HTTP requests</a> and <a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/Work_with_contextual_identities">working with contextual identities</a>, you'll find a range of tutorials to get you started.</p></div></section><section aria-labelledby="firefox_workflow_2"><h2 id="firefox_workflow_2"><a href="#firefox_workflow_2">Firefox workflow</a></h2><div class="section-content"><p>When you are ready to create your extension for Firefox or port your Chrome extension, head over to <a href="https://extensionworkshop.com/" class="external" target="_blank">Extension Workshop</a>. It has details on:</p> <ul> <li>The Firefox workflow, such as <a href="https://extensionworkshop.com/documentation/develop/temporary-installation-in-firefox/" class="external" target="_blank">temporarily installing extensions during development</a>, <a href="https://extensionworkshop.com/documentation/develop/debugging/" class="external" target="_blank">debugging</a>, <a href="https://extensionworkshop.com/documentation/develop/request-the-right-permissions/" class="external" target="_blank">request the right permissions</a>, and more.</li> <li>The <a href="https://extensionworkshop.com/documentation/develop/getting-started-with-web-ext/" class="external" target="_blank">web-ext</a> developer tool.</li> <li><a href="https://extensionworkshop.com/documentation/develop/porting-a-google-chrome-extension/" class="external" target="_blank">Porting a Google Chrome extension</a>, <a href="https://extensionworkshop.com/documentation/develop/differences-between-desktop-and-android-extensions/" class="external" target="_blank">differences between desktop and Android</a>, and more.</li> <li><a href="https://extensionworkshop.com/documentation/publish/" class="external" target="_blank">Publishing and distribution overview</a>, <a href="https://extensionworkshop.com/documentation/publish/promoting-your-extension/" class="external" target="_blank">promoting your extension</a>, the <a href="https://extensionworkshop.com/documentation/manage/" class="external" target="_blank">extension lifecycle best practices</a>, and more.</li> </ul></div></section><section aria-labelledby="reference"><h2 id="reference"><a href="#reference">Reference</a></h2><div class="section-content"></div></section><section aria-labelledby="javascript_apis"><h3 id="javascript_apis"><a href="#javascript_apis">JavaScript APIs</a></h3><div class="section-content"><p>Get comprehensive details about the methods, properties, types, and events for all the <a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/API">JavaScript APIs</a>. There is also detailed information about the compatibility of each API with the major browsers. Most reference pages also include coding examples and links to the extension examples that use the API.</p></div></section><section aria-labelledby="manifest_keys"><h3 id="manifest_keys"><a href="#manifest_keys">Manifest keys</a></h3><div class="section-content"><p>Get full details about the <a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json">manifest keys</a>, including all their properties and settings. There's also detailed information on the <a href="/en-US/docs/Mozilla/Add-ons/WebExtensions/Browser_compatibility_for_manifest.json">compatibility</a> of each key with the major browsers.</p></div></section></article><aside class="article-footer"><div class="article-footer-inner"><div class="svg-container"><svg xmlns="http://www.w3.org/2000/svg" width="162" height="162" viewBox="0 0 162 162" fill="none" role="none"><mask id="b" fill="#fff"><path d="M97.203 47.04c8.113-7.886 18.004-13.871 28.906-17.492a78 78 0 0 1 33.969-3.39c11.443 1.39 22.401 5.295 32.024 11.411s17.656 14.28 23.476 23.86c5.819 9.579 9.269 20.318 10.083 31.385a69.85 69.85 0 0 1-5.387 32.44c-4.358 10.272-11.115 19.443-19.747 26.801-8.632 7.359-18.908 12.709-30.034 15.637l-6.17-21.698c7.666-2.017 14.746-5.703 20.694-10.773 5.948-5.071 10.603-11.389 13.606-18.467a48.14 48.14 0 0 0 3.712-22.352c-.561-7.625-2.938-15.025-6.948-21.625s-9.544-12.226-16.175-16.44-14.181-6.904-22.065-7.863a53.75 53.75 0 0 0-23.405 2.336c-7.513 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2.512 0 4.812 1.522 4.812 4.84v6.402h1.863v3.044h-.005Zm9.036.307c-4.314 0-7.296-2.635-7.296-7.106 0-4.096 2.484-7.481 7.514-7.481s7.481 3.38 7.481 7.29c0 4.472-3.228 7.297-7.699 7.297Zm22.578-.307H51.942l-.403-2.11 7.7-8.846h-4.376l-.621 2.17-2.888-.313.498-4.907h12.294l.313 2.11-7.767 8.852h4.533l.654-2.172 3.167.308-.872 4.908Zm7.99 0h-4.191v-5.03h4.19v5.03Zm0-8.976h-4.191v-5.03h4.19v5.03Zm2.618 8.976 6.054-21.358h3.945l-6.054 21.358h-3.945Zm8.136 0 6.048-21.358h3.945l-6.054 21.358h-3.939Zm21.486.307c-1.863 0-2.887-1.085-3.072-2.792-.805 1.427-2.232 2.792-4.498 2.792-2.02 0-4.314-1.085-4.314-4.006 0-3.447 3.323-4.253 6.518-4.253.778 0 1.584.034 2.3.124v-.465c0-1.427-.034-3.133-2.3-3.133-.84 0-1.488.061-2.143.402l-.453 1.578-3.195-.34.549-3.224c2.45-.996 3.692-1.27 5.992-1.27 3.01 0 5.556 1.55 5.556 4.75v6.083c0 .805.314 1.085.963 1.085.184 0 .375-.034.587-.095l.034 2.11a5.432 5.432 0 0 1-2.524.654Z" fill="currentColor"></path></svg></a><ul class="footer-moz-list"><li 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href="https://foundation.mozilla.org/">Mozilla Foundation</a>.<br/>Portions of this content are ©1998–2024 by individual mozilla.org contributors. Content available under <a href="/en-US/docs/MDN/Writing_guidelines/Attrib_copyright_license">a Creative Commons license</a>.</p></div></div></footer></div><script type="application/json" id="hydration">{"url":"/en-US/docs/Mozilla/Add-ons/WebExtensions","doc":{"isMarkdown":true,"isTranslated":false,"isActive":true,"flaws":{},"title":"Browser extensions","mdn_url":"/en-US/docs/Mozilla/Add-ons/WebExtensions","locale":"en-US","native":"English (US)","sidebarHTML":"\n <ol>\n <li class=\"section\"><em><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions\" aria-current=\"page\">Browser extensions</a></em></li>\n <li>\n <details>\n <summary>Getting started</summary>\n <ol>\n <li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/What_are_WebExtensions\">What are extensions?</a></li>\n<li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/Your_first_WebExtension\">Your first extension</a></li>\n<li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/Your_second_WebExtension\">Your second extension</a></li>\n<li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/Anatomy_of_a_WebExtension\">Anatomy of an extension</a></li>\n<li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/Examples\">Example extensions</a></li>\n<li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/What_next\">What next?</a></li>\n </ol>\n </details>\n </li>\n <li>\n <details>\n <summary>Concepts</summary>\n <ol>\n <li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/API\">JavaScript APIs</a></li>\n<li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/Content_scripts\">Content scripts</a></li>\n<li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/Background_scripts\">Background scripts</a></li>\n<li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/Match_patterns\">Match patterns</a></li>\n<li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/Working_with_files\">Work with files</a></li>\n<li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/Internationalization\">Internationalization</a></li>\n<li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/Content_Security_Policy\">Content Security Policy</a></li>\n<li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/Native_messaging\">Native messaging</a></li>\n<li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/Differences_between_API_implementations\">Differences between API implementations</a></li>\n<li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/Chrome_incompatibilities\">Chrome incompatibilities</a></li>\n </ol>\n </details>\n </li>\n <li>\n <details>\n <summary>User interface</summary>\n <ol>\n <li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/user_interface\">User interface</a></li>\n<li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/user_interface/Toolbar_button\">Toolbar button</a></li>\n<li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/user_interface/Page_actions\">Address bar button</a></li>\n<li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/user_interface/Sidebars\">Sidebars</a></li>\n<li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/user_interface/Context_menu_items\">Context menu items</a></li>\n<li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/user_interface/Options_pages\">Options page</a></li>\n<li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/user_interface/Extension_pages\">Extension pages</a></li>\n<li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/user_interface/Notifications\">Notifications</a></li>\n<li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/user_interface/Omnibox\">Address bar suggestions</a></li>\n<li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/user_interface/devtools_panels\">devtools panels</a></li>\n </ol>\n </details>\n </li>\n <li>\n <details>\n <summary>How to</summary>\n <ol>\n <li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/Intercept_HTTP_requests\">Intercept HTTP requests</a></li>\n<li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/Modify_a_web_page\">Modify a web page</a></li>\n<li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/Safely_inserting_external_content_into_a_page\">Insert external content</a></li>\n<li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/Sharing_objects_with_page_scripts\">Share objects with page scripts</a></li>\n<li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/Add_a_button_to_the_toolbar\">Add a button to the toolbar</a></li>\n<li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/Implement_a_settings_page\">Implement a settings page</a></li>\n<li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/Working_with_the_Tabs_API\">Work with the Tabs API</a></li>\n<li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/Work_with_the_Bookmarks_API\">Work with the Bookmarks API</a></li>\n<li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/Work_with_the_Cookies_API\">Work with the Cookies API</a></li>\n<li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/Work_with_contextual_identities\">Work with contextual identities</a></li>\n<li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/Interact_with_the_clipboard\">Interact with the clipboard</a></li>\n<li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/Extending_the_developer_tools\">Extend the developer tools</a></li>\n<li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/Build_a_cross_browser_extension\">Build a cross-browser extension</a></li>\n </ol>\n </details>\n </li>\n <li>\n <details>\n <summary>JavaScript APIs</summary>\n <ol><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/Browser_support_for_JavaScript_APIs\">Browser support for JavaScript APIs</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/API/action\">action</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/API/alarms\">alarms</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/API/bookmarks\">bookmarks</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/API/browserAction\">browserAction</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/API/browserSettings\">browserSettings</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/API/browsingData\">browsingData</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/API/captivePortal\">captivePortal</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/API/clipboard\">clipboard</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/API/commands\">commands</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/API/contentScripts\">contentScripts</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/API/contextualIdentities\">contextualIdentities</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/API/cookies\">cookies</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/API/declarativeNetRequest\">declarativeNetRequest</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/API/devtools\">devtools</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/API/dns\">dns</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/API/dom\">dom</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/API/downloads\">downloads</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/API/events\">events</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/API/extension\">extension</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/API/extensionTypes\">extensionTypes</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/API/find\">find</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/API/history\">history</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/API/i18n\">i18n</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/API/identity\">identity</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/API/idle\">idle</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/API/management\">management</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/API/menus\">menus</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/API/notifications\">notifications</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/API/omnibox\">omnibox</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/API/pageAction\">pageAction</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/API/permissions\">permissions</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/API/pkcs11\">pkcs11</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/API/privacy\">privacy</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/API/proxy\">proxy</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/API/runtime\">runtime</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/API/scripting\">scripting</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/API/search\">search</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/API/sessions\">sessions</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/API/sidebarAction\">sidebarAction</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/API/storage\">storage</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/API/tabs\">tabs</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/API/theme\">theme</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/API/topSites\">topSites</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/API/types\">types</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/API/userScripts\">userScripts</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/API/webNavigation\">webNavigation</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/API/webRequest\">webRequest</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/API/windows\">windows</a></li></ol>\n </details>\n </li>\n <li>\n <details>\n <summary>Manifest keys</summary>\n <ol>\n <li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json\">manifest.json</a></li>\n </ol>\n <ol><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json/action\">action</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json/author\">author</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json/background\">background</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json/browser_action\">browser_action</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json/browser_specific_settings\">browser_specific_settings</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json/chrome_settings_overrides\">chrome_settings_overrides</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json/chrome_url_overrides\">chrome_url_overrides</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json/commands\">commands</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json/content_scripts\">content_scripts</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json/content_security_policy\">content_security_policy</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json/declarative_net_request\">declarative_net_request</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json/default_locale\">default_locale</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json/description\">description</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json/developer\">developer</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json/devtools_page\">devtools_page</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json/dictionaries\">dictionaries</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json/externally_connectable\">externally_connectable</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json/homepage_url\">homepage_url</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json/host_permissions\">host_permissions</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json/icons\">icons</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json/incognito\">incognito</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json/manifest_version\">manifest_version</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json/name\">name</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json/offline_enabled\">offline_enabled</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json/omnibox\">omnibox</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json/optional_host_permissions\">optional_host_permissions</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json/optional_permissions\">optional_permissions</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json/options_page\">options_page</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json/options_ui\">options_ui</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json/page_action\">page_action</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json/permissions\">permissions</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json/protocol_handlers\">protocol_handlers</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json/short_name\">short_name</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json/sidebar_action\">sidebar_action</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json/storage\">storage</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json/theme\">theme</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json/theme_experiment\">theme_experiment</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json/user_scripts\">user_scripts</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json/version\">version</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json/version_name\">version_name</a></li><li><a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json/web_accessible_resources\">web_accessible_resources</a></li></ol>\n </details>\n </li>\n <li>\n <details>\n <summary>Extension Workshop</summary>\n <ol>\n <li><a href=\"https://extensionworkshop.com/documentation/develop/\">Develop</a></li>\n <li><a href=\"https://extensionworkshop.com/documentation/publish/\">Publish</a></li>\n <li><a href=\"https://extensionworkshop.com/documentation/manage/\">Manage</a></li>\n <li><a href=\"https://extensionworkshop.com/documentation/enterprise/\">Enterprise</a></li>\n </ol>\n </details>\n </li>\n <li class=\"section\"><a href=\"/en-US/docs/Mozilla/Add-ons/Contact_us\">Contact us</a></li>\n <li>\n <details>\n <summary>Channels</summary>\n <ol>\n <li><a href=\"https://blog.mozilla.org/addons\">Add-ons blog</a></li>\n <li><a href=\"https://discourse.mozilla.org/c/add-ons\">Add-ons forum</a></li>\n <li><a href=\"https://chat.mozilla.org/#/room/%23addons:mozilla.org\">Add-ons chat</a></li>\n </ol>\n </details>\n </li>\n </ol>\n","sidebarMacro":"AddonSidebar","body":[{"type":"prose","value":{"id":null,"title":null,"isH3":false,"content":"<p>Extensions, or add-ons, can modify and enhance the capability of a browser. Extensions for Firefox are built using the WebExtensions API cross-browser technology.</p>\n<p>The technology for extensions in Firefox is, to a large extent, compatible with the <a href=\"https://developer.chrome.com/docs/extensions/reference/\" class=\"external\" target=\"_blank\">extension API</a> supported by Chromium-based browsers (such as Google Chrome, Microsoft Edge, Opera, Vivaldi). In most cases, extensions written for Chromium-based browsers run in Firefox with <a href=\"https://extensionworkshop.com/documentation/develop/porting-a-google-chrome-extension/\" class=\"external\" target=\"_blank\">just a few changes</a>.</p>"}},{"type":"prose","value":{"id":"key_resources","title":"Key resources","isH3":false,"content":"<dl>\n <dt id=\"guides\"><a href=\"#guides\">Guides</a></dt>\n <dd>\n <p>Whether you're just beginning or looking for more advanced advice, learn about how extensions work and use the WebExtensions API from our extensive range of <a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/What_are_WebExtensions\">tutorials and guides</a>.</p>\n </dd>\n <dt id=\"references\"><a href=\"#references\">References</a></dt>\n <dd>\n <p>Get comprehensive details about the methods, properties, types, and events of the <a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/Browser_support_for_JavaScript_APIs\">WebExtensions APIs</a> and full details about the <a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json\">manifest keys</a>.</p>\n </dd>\n <dt id=\"firefox_workflow\"><a href=\"#firefox_workflow\">Firefox workflow</a></dt>\n <dd>\n <p>Discover how to build and publish extensions for Firefox: get the lowdown on developer tools, publication and distribution, and porting on <a href=\"https://extensionworkshop.com/\" class=\"external\" target=\"_blank\">Extension Workshop</a>.</p>\n </dd>\n</dl>\n<div class=\"notecard note\">\n <p><strong>Note:</strong> If you have ideas or questions or need help, you can reach us on the <a href=\"https://discourse.mozilla.org/c/add-ons/35\" class=\"external\" target=\"_blank\">community forum</a> or in the <a href=\"https://matrix.to/#/!CuzZVoCbeoDHsxMCVJ:mozilla.org?via=mozilla.org&via=matrix.org&via=humanoids.be\" class=\"external\" target=\"_blank\">Add-ons Room</a> on <a href=\"https://wiki.mozilla.org/Matrix\" class=\"external\" target=\"_blank\">Matrix</a>.</p>\n</div>"}},{"type":"prose","value":{"id":"get_started","title":"Get started","isH3":false,"content":"<p>Discover <a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/What_are_WebExtensions\">what extensions can do</a> before building <a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/Your_first_WebExtension\">your first extension.</a> Learn about the <a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/Anatomy_of_a_WebExtension\">anatomy of an extension</a> and get an overview of the <a href=\"https://extensionworkshop.com/documentation/develop/firefox-workflow-overview/\" class=\"external\" target=\"_blank\">extension development and publication workflow, Firefox style</a>. Explore a little deeper with a comprehensive selection of <a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/Examples\">example extensions</a> that you can run right in Firefox.</p>"}},{"type":"prose","value":{"id":"concepts","title":"Concepts","isH3":false,"content":"<p>Get detailed information on the concept that underpin extensions <a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/API\">from an overview of the JavaScript API</a>, through <a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/Content_scripts\">content scripts,</a> <a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/Match_patterns\">match patterns</a>, <a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/Working_with_files\">working with files</a>, <a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/Internationalization\">internationalization</a>, and <a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/Content_Security_Policy\">content security policy</a>, to more advanced subjects such as <a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/Native_messaging\">native messaging</a>, <a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/Extending_the_developer_tools\">using the devtools APIs</a>, and <a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/Native_manifests\">native manifests</a>.</p>"}},{"type":"prose","value":{"id":"user_interface","title":"User interface","isH3":false,"content":"<p>Discover all the <a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/user_interface\">user interface</a> components you can use in your extensions, with coding examples and tips.</p>"}},{"type":"prose","value":{"id":"how_to","title":"How to","isH3":false,"content":"<p>From patterns you'll regularly use such as <a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/Working_with_the_Tabs_API\">work with the Tabs API</a> and <a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/Add_a_button_to_the_toolbar\">adding a button to the toolbar</a> to more advanced topics such as <a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/Intercept_HTTP_requests\">intercepting HTTP requests</a> and <a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/Work_with_contextual_identities\">working with contextual identities</a>, you'll find a range of tutorials to get you started.</p>"}},{"type":"prose","value":{"id":"firefox_workflow_2","title":"Firefox workflow","isH3":false,"content":"<p>When you are ready to create your extension for Firefox or port your Chrome extension, head over to <a href=\"https://extensionworkshop.com/\" class=\"external\" target=\"_blank\">Extension Workshop</a>. It has details on:</p>\n<ul>\n <li>The Firefox workflow, such as <a href=\"https://extensionworkshop.com/documentation/develop/temporary-installation-in-firefox/\" class=\"external\" target=\"_blank\">temporarily installing extensions during development</a>, <a href=\"https://extensionworkshop.com/documentation/develop/debugging/\" class=\"external\" target=\"_blank\">debugging</a>, <a href=\"https://extensionworkshop.com/documentation/develop/request-the-right-permissions/\" class=\"external\" target=\"_blank\">request the right permissions</a>, and more.</li>\n <li>The <a href=\"https://extensionworkshop.com/documentation/develop/getting-started-with-web-ext/\" class=\"external\" target=\"_blank\">web-ext</a> developer tool.</li>\n <li><a href=\"https://extensionworkshop.com/documentation/develop/porting-a-google-chrome-extension/\" class=\"external\" target=\"_blank\">Porting a Google Chrome extension</a>, <a href=\"https://extensionworkshop.com/documentation/develop/differences-between-desktop-and-android-extensions/\" class=\"external\" target=\"_blank\">differences between desktop and Android</a>, and more.</li>\n <li><a href=\"https://extensionworkshop.com/documentation/publish/\" class=\"external\" target=\"_blank\">Publishing and distribution overview</a>, <a href=\"https://extensionworkshop.com/documentation/publish/promoting-your-extension/\" class=\"external\" target=\"_blank\">promoting your extension</a>, the <a href=\"https://extensionworkshop.com/documentation/manage/\" class=\"external\" target=\"_blank\">extension lifecycle best practices</a>, and more.</li>\n</ul>"}},{"type":"prose","value":{"id":"reference","title":"Reference","isH3":false,"content":""}},{"type":"prose","value":{"id":"javascript_apis","title":"JavaScript APIs","isH3":true,"content":"<p>Get comprehensive details about the methods, properties, types, and events for all the <a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/API\">JavaScript APIs</a>. There is also detailed information about the compatibility of each API with the major browsers. Most reference pages also include coding examples and links to the extension examples that use the API.</p>"}},{"type":"prose","value":{"id":"manifest_keys","title":"Manifest keys","isH3":true,"content":"<p>Get full details about the <a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/manifest.json\">manifest keys</a>, including all their properties and settings. There's also detailed information on the <a href=\"/en-US/docs/Mozilla/Add-ons/WebExtensions/Browser_compatibility_for_manifest.json\">compatibility</a> of each key with the major browsers.</p>"}}],"toc":[{"text":"Key resources","id":"key_resources"},{"text":"Get started","id":"get_started"},{"text":"Concepts","id":"concepts"},{"text":"User interface","id":"user_interface"},{"text":"How to","id":"how_to"},{"text":"Firefox workflow","id":"firefox_workflow_2"},{"text":"Reference","id":"reference"}],"summary":"Extensions, or add-ons, can modify and enhance the capability of a browser. Extensions for Firefox are built using the WebExtensions API cross-browser technology.","popularity":0.0137,"modified":"2024-07-26T03:27:04.000Z","other_translations":[{"locale":"de","title":"Browsererweiterungen","native":"Deutsch"},{"locale":"es","title":"Extensiones del navegador","native":"Español"},{"locale":"fr","title":"WebExtensions","native":"Français"},{"locale":"ja","title":"ブラウザー拡張機能","native":"日本語"},{"locale":"ko","title":"WebExtensions","native":"한국어"},{"locale":"pt-BR","title":"Extensões do navegador","native":"Português (do Brasil)"},{"locale":"ru","title":"Расширения браузера","native":"Русский"},{"locale":"zh-CN","title":"浏览器扩展","native":"中文 (简体)"},{"locale":"zh-TW","title":"瀏覽器擴充功能","native":"正體中文 (繁體)"}],"pageType":"landing-page","source":{"folder":"en-us/mozilla/add-ons/webextensions","github_url":"https://github.com/mdn/content/blob/main/files/en-us/mozilla/add-ons/webextensions/index.md","last_commit_url":"https://github.com/mdn/content/commit/668b38a4f6cd96609b9a969fe4653b46aec4e712","filename":"index.md"},"short_title":"Browser extensions","parents":[{"uri":"/en-US/docs/Mozilla","title":"Mozilla"},{"uri":"/en-US/docs/Mozilla/Add-ons","title":"Add-ons"},{"uri":"/en-US/docs/Mozilla/Add-ons/WebExtensions","title":"Browser extensions"}],"pageTitle":"Browser extensions - Mozilla | MDN","noIndexing":false}}</script></body></html>