# Firefox 156.0b1

- Product: Firefox (https://whatsnew.fyi/product/firefox)
- Vendor: Mozilla
- Date: 2026-08-31
- Version: 156.0b1
- Original notes: https://www.mozilla.org/en-US/firefox/156.0beta/releasenotes/
- Permalink: https://whatsnew.fyi/product/firefox/releases/156.0b1
- Labels: Pre-release

What's New is an index, not a publisher: every entry below links to the vendor's own release notes, which are the authoritative source. Entries are labelled where they are hand-curated sample data, pre-releases, or drawn from a secondary source such as a developer blog.

Reuse: the summaries, labels and curation here are © What's New. Quote freely with attribution and a link back; wholesale republication of the corpus is not permitted — terms: https://whatsnew.fyi/terms. The vendors' own release notes remain their publishers'.

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- **added** — Firefox on macOS can now be set to open automatically when the computer starts up from the Startup section of Settings
- **changed** — Improved memory and CPU usage when Firefox displays large JPEG images scaled down to fit a page
- **added** — Localized Wikipedia and occasional sponsored suggestions in the address bar are now available in France, Germany, and Italy
- **added** — On Firefox for Android, the media notification now has previous and next buttons and a timeline for seeking through audio and video
- **changed** — On Firefox for Android, sharing now uses Android's own share sheet on Android 14 and later with options like Send tab to device and Scan QR code
- **fixed** — On Windows devices with ARM64 processors, WebRTC video calls may now use hardware H264 decoding instead of falling back to software
- **fixed** — Fixed dragging an inline image to a new position in a rich-text editor replacing it with a long line of text instead of moving it
- **fixed** — On all devices, WebRTC video calls may now use hardware AV1 decoding instead of falling back to software
- **fixed** — Fixed high-sample-rate FLAC audio in MP4 failing to play on sites such as Bilibili
- **fixed** — Fixed the find bar becoming permanently unavailable in a tab after reversing the panes in Split View
- **fixed** — Fixed an issue on Windows where Firefox could block an auto-hiding taskbar from showing
- **fixed** — On Firefox for Android, fixed an issue that could cause Firefox to crash when selecting files from some Android file providers
- **fixed** — Fixed subtitles not appearing in the Picture-in-Picture window when they are turned on in the video player after Picture-in-Picture has opened
- **fixed** — On Firefox for Android, fixed an issue where the date picker could allow selecting dates before the minimum allowed date when a maximum date was also specified
- **changed** — Firefox's built-in PDF viewer now starts up to 45% faster
- **changed** — The FirefoxHome policy now has a Widgets option letting administrators control whether the new tab page productivity widgets are available
- **added** — The SitePolicies policy now supports DisableServiceWorkers letting administrators block service worker registration on specific sites
- **changed** — The Windows installer now resolves /INI= paths relative to the installer itself
- **fixed** — Fixed the DontCheckDefaultBrowser and DefaultBrowserSettingEnabled policies being ignored when Firefox started with a new profile
- **changed** — text-box-trim now uses the font metrics of a ::first-line pseudo-element when one applies, matching other browsers and the specification

###### New
- Firefox on macOS can now be set to open automatically when the computer starts up, from the Startup section of Settings.
- Improved memory and CPU usage when Firefox displays large JPEG images scaled down to fit a page.
- Localized Wikipedia and occasional sponsored suggestions in the address bar are now available in France, Germany, and Italy. These suggestions can be turned off in Firefox Suggest settings.
- On Firefox for Android, the media notification now has previous and next buttons, and a timeline for seeking through audio and video.
- On Firefox for Android, sharing now uses Android's own share sheet on Android 14 and later, including options like Send tab to device and Scan QR code. Older Android versions keep the existing in-app share screen.
###### Fixed
- On Windows devices with ARM64 processors, WebRTC video calls may now use hardware H264 decoding instead of falling back to software.
- Fixed dragging an inline image to a new position in a rich-text editor replacing it with a long line of text instead of moving it.
- On all devices, WebRTC video calls may now use hardware AV1 decoding instead of falling back to software.
- Fixed high-sample-rate FLAC audio in MP4 failing to play on sites such as Bilibili.
- Fixed the find bar becoming permanently unavailable in a tab after reversing the panes in Split View.
- Fixed an issue on Windows where Firefox could block an auto-hiding taskbar from showing.
- On Firefox for Android, fixed an issue that could cause Firefox to crash when selecting files from some Android file providers.
- Fixed subtitles not appearing in the Picture-in-Picture window when they are turned on in the video player after Picture-in-Picture has opened.
- On Firefox for Android, fixed an issue where the date picker could allow selecting dates before the minimum allowed date when a maximum date was also specified.
###### Changed
- Firefox's built-in PDF viewer now starts up to 45% faster.
###### Enterprise
- The FirefoxHome policy now has a Widgets option, letting administrators control whether the new tab page productivity widgets are available.
- The SitePolicies policy now supports DisableServiceWorkers, letting administrators block service worker registration on specific sites.
- The Windows installer now resolves /INI= paths relative to the installer itself, so deployment tools that unpack to a temporary folder no longer need an absolute path.
- Fixed the DontCheckDefaultBrowser and DefaultBrowserSettingEnabled policies being ignored when Firefox started with a new profile.
###### Developer
- Developer Information
###### Web Platform
- text-box-trim now uses the font metrics of a ::first-line pseudo-element when one applies, matching other browsers and the specification.