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Release Notes

Release Notes tell you what's new in Firefox. As always, we welcome your feedback. You can also file a bug in Bugzilla or see the system requirements of this release.

157.0beta Firefox Beta

September 14, 2026

Version 157.0beta, first offered to Beta channel users on September 14, 2026

Firefox Beta gets updated 3 times a week and as a consequence, the release notes for the Beta channel are updated continuously to reflect features that have reached sufficient maturity to benefit from community feedback and bug reports.

Warning: Features listed here may or may not make a final release of Firefox

In addition to these release notes, you can follow ongoing development via the Firefox Trains website or our @FirefoxBeta Bluesky account.

New

  • Screenshot of Firefox visual refresh

    Firefox's biggest visual refresh in years, internally referenced as Project Nova, is now available on Beta, with a modernized look across the browser chrome, sidebar, and menus built with our updated design system. It also includes:

    • New built-in themes with light and dark versions, so you can personalize the look of Firefox in a click.
    • A new compact mode that reduces toolbar and tab spacing to give you more room for web content, useful on smaller screens and in split-screen layouts.

  • Localized suggestions in your address bar are now available in Austria, Belgium, Czech Republic, Denmark, Finland, Hungary, Ireland, Luxembourg, Netherlands, Norway, Poland, Portugal, Slovakia, Spain, Sweden, and Switzerland. You can control the suggestions in your Firefox Suggest settings.

Fixed

  • On all devices, WebRTC video calls may now use hardware AV1 decoding instead of falling back to software.

  • Fixed the address bar searching for the typed text instead of opening the selected suggestion when a page was still loading, such as shortly after Firefox started.

  • HDR videos encoded as 8bit color formats now properly display as HDR in most cases, this fixes several cases of dull gray looking videos that should have been more vibrant.

  • Improved audio/video synchronization when changing playback rate on HTMLMediaElement.

  • Fixed the Vertical Tabs sidebar not reappearing when the cursor moves to the edge of the screen in full screen mode.

  • Fixed an issue on Windows where making a video full screen would leave the Windows taskbar showing over the video.

Changed

  • You can now use the Tab key to move focus from the address bar to the search bar without focus landing on the search bar's search engine button first.

  • Amazon is no longer included as a built-in search engine. You can add it as a custom search engine in Firefox’s search settings. Learn more.

Developer

Web Platform

  • Firefox now supports the at-rule() function for @supports. This allows authors to detect for browser support of specific at-rules, such as @supports at-rule(@scope).

  • Firefox now supports the chain value for the CSS overscroll-behavior property.

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Other Resources

Developer Information Complete list of changes for this release Press Kit Mozilla and Firefox News Firefox Extended Support Release All Firefox for Desktop Releases Learn more about Firefox