Muokkaa Firefoxia

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.

Opi kuinka tehdä lisäosa

Port a Chrome Extension

Firefox 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.

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Julkaise lisäosasi

Have an add-on ready? Submit your extension or theme to be listed on or sign and distribute your extension on your own.


Write one code base for many browsers

With the WebExtensions API, it’s easy to create extensions that will run on Firefox, Chrome, Opera, and Edge with only a few small changes. Learn more about the differences in extension development between the four major browsers and how you can make your extension cross-browser compatible.

View Best Practices for Cross-Browser Development

Viimeisimmät uutiset

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  • Web-Ext

    A command line tool to build, run, and test extensions.

  • Lisäosan kelpuutus

    Automated code tests for your add-on.

  • Yhteensopivuustesti

    Tarkista nähdäksesi onko laajennuksesi yhteensopiva Firefoxin kanssa.

  • Live Testing

    Temporarily install your extension in Firefox for live testing and debugging.