Add-ons let millions of Firefox users enhance their browsing experience. If you know HTML, JavaScript, and CSS, you already have all the necessary skills to make a great add-on.
Learn How to Make an Add-onFirefox supports WebExtension APIs, which in most cases are compatible with the extension APIs supported by Chrome, Opera and Edge, so your extensions will run in Firefox with just a few changes.
Learn HowHave an add-on ready? Submit your extension or theme to be listed on addons.mozilla.org or sign and distribute your extension on your own.
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