APIActive

WebExtensions API

Cross-browser API for building browser extensions compatible with Firefox and Chromium-based browsers.

Field note

What it does

WebExtensions API enables developers to create extensions that modify and enhance browser capabilities, with compatibility across Firefox, Chrome, Edge, Opera, and Vivaldi.

Capabilities

Available capabilities

Cross-browser compatibility Content scripts Toolbar button HTTP request interception Background scripts Native messaging

WebExtensions API

What it does

Available capabilities

Tags

Ways to use it

Product features

Browser namespace differences

Examples

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