Get the Latest Mozilla Firefox 4 Beta, Test Your Favorite Websites and Add-ons

The latest Mozilla Firefox 4 Beta is now available to download and test. This release delivers improved performance and responsiveness when watching videos on your favorite video websites. We are in the final stages of the Firefox 4 Beta cycle. The team has fixed more than 7,000 bugs since the first beta release.

We are working closely with the community of add-on developers to ensure their Firefox Add-ons are ready to customize the features, look and functionality of Firefox 4 Beta. For more details on how to make your add-ons compatible with Firefox 4 Beta, read this blog post from Firefox Add-ons Developer Relations Lead, Jorge Villalobos.

We couldn’t build Firefox 4 Beta without the help of our millions of beta testers and their feedback, which we welcome as we work to deliver an awesome experience to the more than 400 million Firefox users worldwide.

For more information:
Download Firefox 4 Beta
Learn more about the features
Submit your feedback
Short, to the point FAQ
Long, technical release notes


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