Bring your extension to life

Support your development workflow with these straightforward tools and guides.

Firefox Tools

Development tools

All you need to create extensions for Firefox is a text editor and a version of Firefox to support your testing. Mozilla and the Firefox extension developer community have also created a number of extension development tools that can simplify the coding and testing of your extension.

Chromium-based browser extensions

Get familiar with the webextension-polyfill library if you’re planning on developing for both Firefox and chromium based browsers.

This enables you to switch between the different Firefox and chromium based namespaces and asynchronous call handling methods for each type of browser.

web-ext command line tool

The web-ext tool can help you by:

  • providing features to automatically reload your extension preview as the code changes
  • assist with debugging
  • create extension packages, and more

User Experience

Great user experiences

Having an exceptional user experience is crucial to attracting, and retaining, users of your extension.

RememBear is a great example of an extension with an outstanding user experience.

Make a great first impression

Focus on a slick onboarding flow that gets users up to speed with your extension quickly.

If your extension collects user data during onboarding, make sure you follow the best practices for collecting user data consent. And, it’s important that you request the right permissions.

Put your user first

Keep your users engaged and follow the user experience best practices. And, don’t forget to build an accessible extension, so that everyone can make use of it.

Lastly, building a secure extension is fundamental to delivering an excellent user experience.

Define your value proposition

Users are less likely to install an extension if they don’t understand what it does and what value it adds to their browsing experience. Find out best practices for putting your best foot forward with your extension.

Firefox for Android

Creating browser experiences for Android apps

If you develop Android apps, when you want to include a browser experience in your app you can take advantage of the browser engine that underpins Firefox using the GeckoView Extensions Android library.

Port to Firefox

Chrome To Firefox Extensions

Bring your Chrome extension to Firefox

The Firefox extension environment is highly compatible with chromium-based extension technology. Your extension might already be capable of running on Firefox, or need only a few changes.

Test your extension’s compatibility and check out our porting guide to get started.

Update a legacy Firefox extension

If you have a legacy Firefox extension, you can still find out how to get it up and running on the latest version of Firefox. Check out the porting information for the Add-on SDK and XUL/XPCOM based extensions.