scripting

Inserts JavaScript and CSS into websites. This API offers two approaches to inserting content:

scripting.executeScript(), scripting.insertCSS(), and scripting.removeCSS() that provide for one-off injections.
scripting.registerContentScripts() that registers content scripts dynamically, which can then be retrieved with scripting.getRegisteredContentScripts() and unregistered with scripting.unregisterContentScripts()).

Note: Chrome restricts this API to Manifest V3. Firefox and Safari support this API in Manifest V2 and V3.

This API requires the "scripting" permission and host permission for the target in the tab into which JavaScript or CSS is injected.

Alternatively, you can get permission temporarily in the active tab and only in response to an explicit user action, by asking for the "activeTab" permission. However, the "scripting" permission is still required.

Types

scripting.ContentScriptFilter

Specifies the IDs of scripts to retrieve with scripting.getRegisteredContentScripts() or to unregister with scripting.unregisterContentScripts().

scripting.ExecutionWorld

Specifies the execution environment of a script injected with scripting.executeScript() or registered with scripting.registerContentScripts().

scripting.InjectionTarget

Details of an injection target.

scripting.RegisteredContentScript

Details of a content script to be registered or that is registered.

Functions

scripting.executeScript()

Injects JavaScript code into a page.

scripting.getRegisteredContentScripts()

Gets a list of registered content scripts.

scripting.insertCSS()

Injects CSS into a page.

scripting.registerContentScripts()

Registers a content script for future page loads.

scripting.removeCSS()

Removes CSS which was previously injected into a page by a scripting.insertCSS() call.

scripting.updateContentScripts()

Updates one or more content scripts already registered.

scripting.unregisterContentScripts()

Unregisters one or more content scripts.

Example extensions

beastify

Browser compatibility

Enable JavaScript to view this browser compatibility table.

Note: This API is based on Chromium's chrome.scripting API.

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This page was last modified on Jul 17, 2025 by MDN contributors.

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