Firefox Extension Workshop | Get help creating & publishing Firefox extensions.

Get help creating and publishing Firefox add-ons that make browsing smarter, safer, and faster.
You’ll find the resources you need, whether you’re getting started with extension development, preparing to launch your innovation, or developing a custom enterprise solution.
Get your great idea into the hands of millions of Firefox users. Join an international community of developers. Be supported every step of the way. And, when you build for Firefox first, it’s easy to port your extension to other browsers, saving you valuable development time.
Learn more about extensions
Your extension can control browser tabs. Use the API to open, close, move, hide, and perform other tab management actions.
Learn more about tabs
Use Firefox's powerful built-in search capabilities to open up the web for users from within your own extension.
Learn about enhancing content
Think the browser is missing a feature, such as a built-in calculator, music streaming, or language translation? Add a toolbar button to expose your extension's new capabilities.
View more extension code examples
Explore live extensions
An extension is a simple collection of files that modify the browser’s appearance and behavior. It can add user interface elements, alter content, or perform background tasks that enhance browsing.
Learn more about extension anatomy
Add toolbar buttons, menu choices, and—only in Firefox—sidebars to display additional content. Manage tab behavior and create pop-up windows that respond to user events.
Change webpage content. Remove ads, highlight key words, and reformat elements for readability.
Manage long-term configuration beyond the current tab, and respond to user events such as button clicks and menu selections.
It's easy to create your cross-browser extension for Firefox. Where your development journey begins depends on your skill and experience.
MDN web docs will onboard you to the basics. With tutorials from simple user interface changes to complex event handling, MDN covers the structure and API behind extensions. Once you know the fundamentals, come back here to learn how Firefox takes extension development to the next level.
Learn the fundamentals on MDN
If you know the basics of extension development, you’re ready to create an extension for Firefox. We’ve got all the resources you need right here. Learn about cross-browser development. Get tips on testing. Make user updates smooth and painless.
Mozilla takes the safety and privacy of its users very seriously. Be sure to review and follow these practices and policies so you can make your great idea a reality.
Learn about security best practices
Learn about our policies
Firefox is at the forefront of cross-browser compatibility. Firefox add-ons are built using the WebExtensions API, so your creation will be accessible to users no matter what browser they use.
Learn about browser differences
Port a Google Chrome Extension
See if your extension works in Firefox. Simply upload your .crx file to the Developer Hub.
When you build on Firefox, you build with a community of add-on developers. And they’re eager to share their expertise and answer your questions.
Ask questions in the forum
Join the community conversation
Learn more about the community
Learn about enhancing the API
For developers: @mozamo
For end users: @rockyourfirefox
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