Mozilla Firefox (eo): baixar versions anteriors

Version 157.0.1, first offered to Release channel users on October 6, 2026

Fixed
- Fixed downloads failing on macOS when Firefox is set to ask where to save files but doesn't have permission to access the Downloads folder. (Bug 2077390)
- Fixed the sidebar getting stuck on the Bookmarks or AI Chatbot panel for some users. (Bug 2076296)
- Fixed the Restore from Backup option not appearing during onboarding on Windows. (Bug 2073401)
- Security fix.
- Reference link to 157.0 release notes.

Version 157.0, first offered to Release channel users on September 29, 2026

New
-
Firefox's biggest visual refresh in years is now available, with a modernized look across the browser toolbars, sidebar, menus and individual features, built with our updated design system. It also includes:
- New built-in themes with light and dark versions, to personalize the look of Firefox in one click.
- A new compact mode that reduces toolbar and tab spacing to leave more room for web content, useful on smaller screens and in split-screen layouts.
- WebRTC video calls can now use hardware AV1 decoding on devices that support it, instead of always decoding AV1 video in software.
- Firefox now shows a warning in the site information panel (the shield icon in the address bar) and in Settings when it has been set up to record its encryption keys, which could let other software on the computer read encrypted web traffic.
- Firefox Suggest now offers suggestions in the address bar in Austria, Belgium, Czech Republic, Denmark, Finland, Hungary, Ireland, Luxembourg, Netherlands, Norway, Poland, Portugal, Slovakia, Spain, Sweden, and Switzerland. They can be controlled in the Firefox Suggest settings. Learn more.

Fixed
- Fixed video from phones and tablets appearing sideways or upside down in WebRTC calls.
- 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.
- Fixed some HDR videos encoded in 8-bit color formats looking dull and gray on Windows instead of displaying in HDR.
- Improved audio and video synchronization when repeatedly changing the playback speed of videos, for example on YouTube.
- 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.
- Various security fixes.

Changed
- Pressing Tab now moves focus straight to the text field of the address bar and search bar instead of stopping on the search engine button first. The button can still be reached with Shift+Tab.
- Amazon is no longer included as a built-in search engine. It can still be added as a custom search engine in the search settings. Learn more.
- The updated sidebar is now enabled for everyone. Anyone still using the previous sidebar will keep a similar layout, with the panel switcher at the top of the sidebar. Additionally, the “Show sidebar” option has been removed from Settings.
While we continue to refine the new design, the previous sidebar version can still be restored by setting sidebar.revamp to false in about:config. This also turns off vertical tabs. The preference will remain available until the end of 2027.
- Web page alert(), confirm() and prompt() dialogs, the color and date pickers, and form autocomplete drop-downs now match the page's light or dark color scheme.

Enterprise
- You can find information about policy updates and enterprise-specific bug fixes in the Firefox for Enterprise 157 Release Notes.

Developer

Web Platform
- Firefox now supports the at-rule() function for @supports. This allows authors to detect browser support for specific at-rules, such as @supports at-rule(@scope).
- Firefox now supports the chain value for the CSS overscroll-behavior property.

Community Contributions
- With the release of Firefox 157, we are pleased to welcome the developers who contributed their first code change to Firefox in this release, 21 of whom were brand new volunteers! Please join us in thanking each of these diligent and enthusiastic individuals, and take a look at their contributions:
- Alexander Gankov: 2033184
- Amadi: 2053549, 2053553, 2065302, 2066478
- Andrew: 2031465
- Caleb Pickard: 2058970
- David Torcivia: 2057758
- dchen705: 2065655
- Ekerin Agboola: 2064541
- Giddeon Card: 2067328
- gustavokrm: 2051536
- Hanzala Sohrab: 2068111
- Ivan Smagin: 2061540
- Jieke 

Version 156.0.1, first offered to Release channel users on September 22, 2026

Fixed
- Fixed the NVDA screen reader not announcing address bar buttons when the mouse pointer moves over them. (Bug 2069276)
- Fixed elements inside a link not showing their CSS :active styles while being clicked. (Bug 2067272)
- Fixed Firefox becoming unresponsive on some pages that use CSS anchor positioning. (Bug 2070171)
- Fixed Firefox windows on macOS 27 immediately returning to maximized after being restored by double-clicking the title bar. (Bug 2066632)
- Fixed Firefox leaking system handles on Windows as content processes were started and stopped. (Bug 2069644)
- Reference link to 156.0 release notes.

Version 156.0, first offered to Release channel users on September 15, 2026

New
- Firefox on macOS can now be set to open automatically when the computer starts up, from the Startup section of Settings.
- 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.

Fixed
- Fixed an issue where dragging an image to a new position in a rich-text editor could replace it with a long line of text instead of moving it.
- Fixed high-sample-rate FLAC audio in MP4 failing to play on sites such as Bilibili.
- Fixed subtitles not appearing in the Picture-in-Picture window when they are turned on in the video player after the window has already opened.
- Fixed bookmarks moving out of their folder when the folder and the bookmarks inside it were selected and dragged together in the Bookmarks sidebar.
- Fixed the find bar becoming permanently unavailable in a tab after reversing the panes in Split View.
- Fixed some sites failing to load when DNS over HTTPS is enabled and the site does not support HTTPS.
- Fixed Firefox losing all network connectivity for some users with the built-in VPN enabled.
- Fixed an issue on Windows where Firefox could block an auto-hiding taskbar from showing.
- Various security fixes.

Changed
- Firefox's built-in PDF viewer now starts up to 45% faster.
- Improved memory and CPU usage when Firefox displays large JPEG images scaled down to fit a page.
- On Windows devices with ARM64 processors, WebRTC video calls may now use hardware H264 decoding instead of falling back to software.

Enterprise
- You can find information about policy updates and enterprise-specific bug fixes in the Firefox for Enterprise 156 Release Notes.

Developer

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.

Community Contributions
- With the release of Firefox 156, we are pleased to welcome the developers who contributed their first code change to Firefox in this release, 10 of whom were brand new volunteers! Please join us in thanking each of these diligent and enthusiastic individuals, and take a look at their contributions:
- Aaron Ma: 2063818
- Dominik Bay [:eimann]: 2066736
- ExplodingJoysticks: 1728637, 1890400, 1910664, 1928343, 1944206, 2000658, 2003000, 2059911, 2061541
- Gopalarathnam Venkatesan: 2003172, 2042426, 2062096, 2062952, 2062989
- Hugo Osvaldo Barrera: 2063808
- Kana: 2062133
- Kerissa Grubb: 2042422
- Louis-Philippe Manette: 2062972, 2063867
- Seunghyun An: 2063033
- William McDonald: 1034964

Version 155.0.1, first offered to Release channel users on September 4, 2026

Fixed
- Fixed Firefox becoming unresponsive on some pages that use CSS blur and backdrop filters together. (Bug 2068836)
- Fixed the sidebar not reappearing after restarting Firefox when the "Hide tabs and sidebar" option was turned on. (Bug 2065431)
- Fixed some profile icons not being displayed in the account and application menus. (Bug 2064729, Bug 2067734)
- Fixed the current device being listed among connected devices in the account menu. (Bug 2059763)
- Reference link to 155.0 release notes.

Unresolved
- Standard dynamic range (SDR) video in some formats can appear washed out on macOS. The issue is under investigation and a fix will ship in a future release. (Bug 2068961)

Version 155.0, first offered to Release channel users on September 1, 2026

New
- Smart Window is now available for all users in the USA, Canada, and France to try out! Additionally, Firefox 155 includes many new enhancements:
- New personalized resume conversation starters help users quickly return to topics they’ve been working on.

- Assistant now responds much faster with Exa web search source citations to provide accurate, trustworthy web grounding in roughly 1/5 the time.

- Organize Tabs now suggests better groupings of your related tabs and gives each group a clearer, more descriptive name.

This feature is part of a progressive roll out.
What is a progressive roll out?
Certain new Firefox features are released gradually. This means some users will see the feature before everyone does. This approach helps to get early feedback to catch bugs and improve behavior quickly, meaning more Firefox users overall have a better experience.
- Firefox now shows how many trackers it has blocked in the address bar, making built-in privacy protections easier to see while browsing. The count can be hidden in settings without turning off tracker blocking.
This feature is part of a progressive roll out.
What is a progressive roll out?
Certain new Firefox features are released gradually. This means some users will see the feature before everyone does. This approach helps to get early feedback to catch bugs and improve behavior quickly, meaning more Firefox users overall have a better experience.
- Nintendo Switch Pro and compatible aftermarket controllers now work fully in web games on Windows, with the directional pad and analog sticks correctly mapped.
- Containers can now be reordered in Settings, and the new order is used wherever containers are listed.

- The Translations feature now supports the following languages:
- Marathi
- Urdu

Fixed
- Fixed text disappearing in Microsoft 365 Word Online and other web apps on Linux when typing with certain keyboard layouts.
- Fixed an unnecessary paste confirmation appearing when using the keyboard shortcut to paste without formatting in Google Docs.
- Firefox now recovers from the toolbar and tab strip being left unresponsive when the platform fails to end a tab drag session.
- Fixed text inside buttons not being selectable or copyable, which prevented copying direct messages on X and comments on YouTube.
- Fixed live audio streams such as internet radio stopping when playing in the background.
- Fixed the sound indicator disappearing from a tab that was moved to another window, leaving no way to see or mute what was playing.
- Fixed Firefox preventing Linux systems from going to sleep after a long browsing session.
- Fixed full screen content being letterboxed on MacBooks with a camera notch, most visibly when watching video.
- Fixed arrow-key and Page Up/Down scrolling not working on some pages with embedded content from other sites.
- Fixed characters from some less common scripts appearing as empty boxes on web pages on Windows.
- Fixed WebCodecs VideoEncoder hanging on macOS when encoding a VideoFrame in NV12 format.
- Various security fixes.

Changed
- Firefox now limits CSS to 75 levels of nested blocks and functions, preventing crashes that extremely deep nesting can cause under some circumstances. More deeply nested rules and values no longer parse.
- Firefox now uses firefox-portal-detection.com instead of detectportal.firefox.com to detect captive portals and check network connectivity, so network allowlists referencing the old domain need updating.
- Firefox now opens mailto: links only in response to an explicit user action, so pages can no longer launch the default mail client unprompted.
- PDFs smaller than the paper size can now be enlarged to fill the sheet when printing, by setting the scale above 100%.

Enterprise
- You can find information about policy updates and enterprise-specific bug fixes in the Firefox for Enterprise 155 Release Notes.

Developer
- The Rules View no

Version 154.0.1, first offered to Release channel users on August 25, 2026

Fixed
- Fixed slower access to saved passwords and unexpected Primary Password prompts caused by recent changes to password storage. (Bug 2064411, Bug 2065593, Bug 2063993)
- Fixed an issue where addresses were failing to autofill on some sites. (Bug 2065145, Bug 2063599)
- Fixed Firefox adding a new Start Menu shortcut on Windows every time it started. (Bug 2064652)
- Fixed an issue where connections to local network devices were failing without a permission prompt on some sites loaded over HTTP. (Bug 2059274)
- Fixed a crash that could occur when opening intranet sites that are configured to link to files on a local network share. (Bug 2064648)
- Fixed an issue on Windows where tab titles were cut off at the start when the system font was MS UI Gothic. (Bug 2056856)
- Reference link to 154.0 release notes.

Version 154.0, first offered to Release channel users on August 18, 2026

New
- Firefox's Local Network Access protections now extend to WebSocket connections. Websites that try to open a WebSocket to a device on the local network will now ask for permission first.
- In Smart Window, Firefox can now suggest groups of related tabs and propose a name for each group.

This feature is part of a progressive roll out.
What is a progressive roll out?
Certain new Firefox features are released gradually. This means some users will see the feature before everyone does. This approach helps to get early feedback to catch bugs and improve behavior quickly, meaning more Firefox users overall have a better experience.
- Local Firefox profile backups are now available on macOS in addition to Windows and Linux, and backups can be restored across all three platforms.
- Sites can now be exempted from having their cookies and site data cleared on shutdown without also being exempted from tracking protection and other cookie restrictions.
- The full-page Translations feature now translates <iframe> content.
- The full-page Translations feature now runs language identification on all page loads, resulting in an improved experience for offering translations to users.
- Windows users can now choose a different Firefox app icon in Settings. This is not yet available for MSIX installations, macOS, or Linux, but is coming soon.
- The address bar now includes a Manage AI quick action that opens the AI controls in Settings.
- Performing a hard reload on a page (holding Shift while clicking the Refresh button) now also clears and updates its cached favicons.

Fixed
- Fixed an issue on macOS where closing a browser window could leave behind an invisible window that continued to capture mouse clicks over the area where it used to be.
- Fixed an issue on Windows where an auto-hiding taskbar would not appear until the Firefox window had been minimized and restored after launch.
- Fixed an issue where the Windows taskbar would appear in front of a full screen Picture-in-Picture window.
- Fixed the Vertical Tabs sidebar staying visible in full screen mode. It now hides along with the toolbars and reappears when the cursor moves to the edge of the screen.
- Fixed PDF documents not being scaled correctly in print preview when the Fit to Page Width option is used.
- Various security fixes.

Changed
- Video seeking is now significantly faster on all operating systems, making it quicker to jump to a point in a video.
- Text selected in a PDF is now highlighted the same way as text on a web page, and the highlight color follows operating system settings such as high-contrast mode.
- Firefox View is moving out of the toolbar by default for new profiles and for profiles where it hasn't been used recently. It can still be opened from List all tabs > View all tabs, or added back from the Customize toolbar menu.

Enterprise
- You can find information about policy updates and enterprise-specific bug fixes in the Firefox for Enterprise 154 Release Notes.

Developer
- The JSON Viewer now shows a breadcrumb path at the bottom for the selected entry.

Web Platform
- Firefox now supports the text-box-trim and text-box-edge CSS properties, and the associated text-box shorthand. These properties control the leading space above and below text, enabling simpler and more consistent vertical spacing and alignment.
- Firefox now supports the sibling-index() and sibling-count() CSS functions. These functions allow an element to be styled with calculations that use its index among its siblings and its total count of siblings (including itself), respectively.
- Added a time picker user interface to <input type="time"> and <input type="datetime-local">, making selecting a time more accessible and intuitive.
- Added support for the No-Vary-Search HTTP response header for the HTTP disk cache. Servers can now declare which URL query parameters are irrelevant to the response, allowing Firefox 

We're still preparing the notes for this release, and will post them here when they are ready. Please check back later.

Version 153.0.3, first offered to Release channel users on August 4, 2026

New
- Smart Window includes several enhancements:
- The suggestion list now shows more results, making it easier to find history and switch to open tabs. (Bug 2019042)
- The assistant can now answer questions directly using web search results from Exa, instead of handing off to a search engine. (Bug 2046183, Bug 2044385)
This feature is part of a progressive roll out.
What is a progressive roll out?
Certain new Firefox features are released gradually. This means some users will see the feature before everyone does. This approach helps to get early feedback to catch bugs and improve behavior quickly, meaning more Firefox users overall have a better experience.

Fixed
- Fixed audio and video failing to play, or hanging when seeking, on websites that load media from a Blob URL. (Bug 2056444)
- Fixed Internet shortcuts dragged from Firefox to the desktop being marked as untrusted on Windows, which caused a security warning every time they were opened. (Bug 2056865)
- Fixed the Bookmarks, History, and other sidebars failing to open when the sidebar is hidden and the password manager has been turned off by an enterprise policy. (Bug 2056857)
- Fixed a Mozilla VPN upgrade offer appearing for people in regions where Mozilla VPN is not sold. (Bug 2058264)
- Fixed frequent Inspector crashes in the Developer Tools on pages where an extension content script had added event listeners. (Bug 2042101)
- Fixed a rare case on Windows where starting Firefox while a partial update was still being applied could leave the installation broken and unable to start. (Bug 2058197, Bug 2058594)
- Reference link to 153.0.1 release notes.

Version 153.0.1, first offered to Release channel users on July 28, 2026

Fixed
- Addressed a startup crash on Windows that could occur after updating Firefox, when some of the application's internal files could not be loaded. Firefox should now start in these cases, although parts of the interface may not display correctly until a further update completes (Bug 2056926).
- Fixed audio playing silently on some music and audio streaming sites after pausing and resuming playback (Bug 2053586).
- Fixed the New Tab page background flashing a few seconds after the page loaded when a custom wallpaper was in use (Bug 2056650).
- Fixed a crash that could occur when a page loaded a frame using a javascript: address (Bug 2054485).
- Fixed a crash that could occur while typing text in an editable area of a page (Bug 2053867).
- Fixed a search engine you had already installed yourself being labeled as "New" when Firefox later started offering the same engine (Bug 2053710).
- Improved pointer lock, used by games and other immersive web content, so that the mouse pointer is less likely to escape the Firefox window (Bug 1255338, Bug 2040628).
- Fixed an issue in the Inspector's Rules view where pseudo-elements could only be expanded once per selected element (Bug 2054525).
- Fixed View Page Source failing to load blob: documents (Bug 2054428).
- Fixed View Page Source timing out on documents that inherit their origin, such as frames using the srcdoc attribute (Bug 2054487).
- Reference link to 153.0 release notes.

Unresolved
- Some Windows users may experience a crash on startup after updating, caused by an incomplete update leaving the Firefox installation in an inconsistent state (Bug 1681745). If you are affected, downloading Firefox from firefox.com and installing it over your existing installation will repair it. Your bookmarks, passwords and other data are stored separately and will not be affected.

Version 153.0, first offered to Release channel users on July 21, 2026

New
- High Dynamic Range (HDR) video playback is now available on Windows - this feature needs HDR mode enabled for the display in Windows Settings - Display. Laptop displays that only offer "HDR video streaming" are not supported at this time. Some videos recorded on phones in certain orientations are currently not shown as HDR.
- Containers let you keep separate parts of your online life (work, shopping, personal, banking) logged into different accounts in the same browser window, but keep your cookies and ad tracking isolated inside each container.
- Share any open page with a QR code. Right-click a tab, select Share > Generate QR Code. Great for posters, invitations, banners, and other printed materials.

- It is now possible to merge multiple PDFs by dragging a PDF into the PDF sidebar.
- It is now possible to add images as new pages within PDFs using the Firefox PDF editor.
- Quickly pick and copy a color from any page by typing "pick color", "color picker", or "eyedropper" in the address bar and selecting the "Pick a color" quick action.

- Added support for Apple's system-wide full-screen keyboard command (Globe-F).
- Firefox now verifies and displays Qualified Website Authentication Certificates (QWACs) in accordance with eIDAS regulations.
- Added improved support for videos with overlays so users can more easily access video actions from context menus.
- Firefox now highlights the location permission icon in red whenever a website has access to your location. The permission icon is also now visible on search results pages where it was previously hidden.

- Smart Window:
- See and choose AI models directly from the Smart Window assistant.
- New Tab now includes a familiar address bar for typing websites and searching the web.

This feature is part of a progressive roll out.
What is a progressive roll out?
Certain new Firefox features are released gradually. This means some users will see the feature before everyone does. This approach helps to get early feedback to catch bugs and improve behavior quickly, meaning more Firefox users overall have a better experience.

Firefox Labs
- Firefox Labs can now be opened quickly by typing "labs" or "experiment" in the address bar and selecting the Open Firefox Labs quick action.

- Firefox now offers experimental support for the new JPEG XL image format, which generally provides better compression than WebP, JPEG, PNG, and GIF and is designed to supersede them. You can enable it from the Firefox Labs panel in Settings.

Fixed
- Various security fixes.

Changed
- Extensions can no longer access local files by default. Users can grant or revoke this access via the new "Access local files on your computer" permission, separate from "Access your data for all websites".
- Local Network Access restrictions are now enabled by default for all users. Firefox requires websites to request permission before connecting to devices on your local network or to apps and services on your device.
- Outdated cookie settings have been removed from the Settings UI. Users still in that mode should switch to default behavior "Isolate cross-site cookies". More information

Enterprise
- You can find information about policy updates and enterprise-specific bug fixes in the Firefox for Enterprise 153 Release Notes.

Developer
- A new "Local Mode" setting in the options panel allows developers to load local directories via custom origins. This simplifies testing for APIs that do not function over standard file:// URLs, removing the need to run a local web server. Multiple directory mappings are supported.

Web Platform
- Firefox now supports a limited subset of the non-standard ::-webkit-scrollbar pseudo-element to improve web compatibility:
- Rules with non-zero width/height disable overlay scrollbars for the affected container.
- display: none on ::-webkit-scrollbar behaves like scrollbar-width: none, hiding the scrollbar.
- @suppor

Version 152.0.6, first offered to Release channel users on July 14, 2026

New
- Smart Window includes several enhancements:
- Select text on a page and get quick access to summarize, explain, and more using the built-in assistant. (Bug 2034921)
- Added a row of shortcuts to New Tab, making it easier to get back to sites. (Bug 2048338)
This feature is part of a progressive roll out.
What is a progressive roll out?
Certain new Firefox features are released gradually. This means some users will see the feature before everyone does. This approach helps to get early feedback to catch bugs and improve behavior quickly, meaning more Firefox users overall have a better experience.

Fixed
- Fixed an issue that prevented email tracking protection from being disabled in the redesigned Firefox Settings. (Bug 2049331)
- Fixed a hang that could occur after using a file picker dialog on macOS 26. (Bug 2053177)
- Fixed the homepage not loading for some enterprise configurations that set it using a legacy autoconfig format. (Bug 2047962)
- Various security fixes.
- Reference link to 152.0.5 release notes.

Version 152.0.5, first offered to Release channel users on July 7, 2026

Fixed
- Fixed the Manage payment methods list in Settings appearing empty when a saved payment card had no expiration date. (Bug 2048383)
- Reference link to 152.0.4 release notes.

Version 152.0.4, first offered to Release channel users on June 30, 2026

New
- Smart Window includes several enhancements:
- You can now ask it to close your tabs, with a confirmation step when needed and the option to undo afterward. (Bug 2040769)
- Browsing history results now appear with images. (Bug 2038069)
- When you give feedback on a response, you can now choose from common reasons and preview exactly what will be shared before submitting. (Bug 2033002)
This feature is part of a progressive roll out.
What is a progressive roll out?
Certain new Firefox features are released gradually. This means some users will see the feature before everyone does. This approach helps to get early feedback to catch bugs and improve behavior quickly, meaning more Firefox users overall have a better experience.

Fixed
- Fixed copy, paste, undo, redo, and similar keyboard shortcuts not working inside macOS system dialogs such as the Save and Open panels. (Bug 2040851, Bug 2040844)
- Fixed the Manage Cookies and Site Data dialog opening with an empty list when opened from the Settings search results. (Bug 2041077)
- Fixed keyboard focus landing in the wrong place after following an in-page link, so pressing Tab continues from the link's position as expected. (Bug 2049307)
- Various security fixes.
- Reference link to 152.0.3 release notes.

Version 152.0.3, first offered to Release channel users on June 25, 2026

Fixed
- Fixed an issue that could cause extreme memory usage and freezing on startup for users with language packs installed. (Bug 2049845)
- Reference link to 152.0.2 release notes.

Version 152.0.2, first offered to Release channel users on June 23, 2026

Fixed
- Fixed some Settings section headings showing placeholder text instead of the translated name in certain languages. (Bug 2047983)
- Fixed New Tab content not matching the browser's display language after it was changed. (Bug 2046945)
- Fixed a regression that could break playback of some MP4 video files. (Bug 2047467)
- Fixed a performance regression that could slow down sites performing many encryption and decryption operations at once, such as Proton Drive. (Bug 2046401)
- Reference link to 152.0.1 release notes.

Version 152.0.1, first offered to Release channel users on June 18, 2026

Fixed
- Fixed frequent crashes affecting users with Intel Raptor Lake processors. (Bug 2039575)
- Fixed an issue on macOS where choosing a PDF option, such as "Save as PDF", from the system print dialog would send the job to your printer instead of saving a file. (Bug 2047850)
- Reference link to 152.0 release notes.

Version 152.0, first offered to Release channel users on June 16, 2026

New
- Firefox Settings features a brand-new look with streamlined organization, clearer groupings, and improved navigation for easier customization.

- In Private Browsing windows, you can now temporarily disable tracker blocking for a tab if it's causing a site to break. When you reload a page where trackers were blocked, Firefox shows a message offering to reload without the stricter protections. All other tracking protections stay active.

- You can now mute your browser from the address bar: type "mute" (or "shush" or "sssh") and use the address bar quick action to silence every tab currently playing sound across all Firefox windows.
- Improved support for more advanced cursor movement commands, including those relating to paragraph boundaries, on macOS.
- On Windows and Linux, you can now copy links via the tab context menu by right-clicking a tab and selecting Share > Copy Link, making it easy to copy a link without switching to the tab first. When multiple tabs are selected, you can copy all selected links at once. Windows users still retain access to Microsoft sharing options from the Share menu.
- A "Send tab" toolbar button is now available which can be added via More Tools > Customize Toolbar.
- The following languages are now available for Translations:
- Basque
- Galician
- Firefox builds in Croatian, English (UK), Georgian, Persian, Slovenian, Tajik, Tamil, Tibetan, Turkish, Welsh, and Xhosa now come with a built-in dictionary for the Firefox spellchecker.

Firefox Labs
- Firefox now offers experimental support for the new JPEG XL image format, which generally provides better compression than WebP, JPEG, PNG, and GIF and is designed to supersede them. You can enable it from the Firefox Labs panel in Settings.

Fixed
- Fixed an issue where the Paste option could be missing from context menus when editing content on sites such as Squarespace, LinkedIn, and eBay.
- Improved dragging images from Firefox to the desktop or Finder on macOS — images now save reliably and land where you drop them.
- In multiple monitor situations, the About Firefox window now more reliably opens on the display with the most recently used Firefox window.
- Fixed arrow-key text navigation and word selection commands that moved in the wrong direction in right-to-left text on macOS and Linux.
- Various security fixes.

Changed
- Site zooming via keyboard or mouse now offers more zoom levels in smaller increments than before.
- When a PDF or other file that Firefox opens directly finishes downloading, it now opens in a background tab if you've switched tabs or closed the original page.
- The Tabs from Other Devices panel in the sidebar now lets you open tabs in a new tab or a new container tab from the context menu.

Developer
- Developer Tools now have an option in the Settings panel to toggle the display of comment nodes in the Inspector.

Web Platform
- Web Notifications can now have action buttons via the actions option. They appear as buttons below the notification text or in the Options list on macOS.
- The field-sizing property is now available, allowing form controls to adjust in size to fit their contents.
- Firefox now supports the WebAuthn Related Origin Request feature, which simplifies login flows by making Passkeys usable from multiple domains.
- The Pointer Lock API now supports the unadjustedMovement option, allowing sites to receive raw mouse-movement data unaffected by OS-level acceleration.

Community Contributions
- With the release of Firefox 152, we are pleased to welcome the developers who contributed their first code change to Firefox in this release, 25 of whom were brand new volunteers! Please join us in thanking each of these diligent and enthusiastic individuals, and take a look at their contributions:
- :23rd: 1812100
- :Vincent: 2033780
- Akeem Omosanya: 2031351, 2035252
- Amin Amir: 2031353, 2031355, 2031599, 2033820
- Amine Zroual: 1392125
-

Version 151.0.4, first offered to Release channel users on June 9, 2026

Fixed
- Fixed an issue on Windows where Firefox could become unresponsive when using the back and forward buttons. (Bug 2039866)
- Fixed an issue where Firefox could fall back to software rendering on some older GPUs, reducing graphics performance. (Bug 2043249)
- Fixed a crash on Windows that could occur when Firefox interacted with accessibility services. (Bug 204330)
- Fixed an issue where some text input fields could incorrectly show a resize handle. (Bug 2044051)
- Reference link to 151.0.3 release notes.

Version 151.0.3, first offered to Release channel users on June 2, 2026

Fixed
- Fixed an issue where selecting or pasting text in a text field inside a table cell could disrupt the page layout. (Bug 2041235)
- Fixed an issue where the VPN toolbar button icon could appear larger than intended. (Bug 2042454)
- Reference link to 151.0.2 release notes.

Version 151.0.2, first offered to Release channel users on May 26, 2026

Fixed
- Fixed an issue on macOS where smart cards and security keys could fail to load certificates automatically. (Bug 2041208)
- Fixed an issue where adding another tab to an existing Split View could unexpectedly close it. (Bug 2039795)
- Fixed an issue where Split View would close instead of switching tabs when using the "Switch to Tab" option from the address bar. (Bug 2039787)
- Fixed a crash on Windows that occurred when using the Sogou input method to type Simplified Chinese. (Bug 2039203)
- Fixed an issue where Firefox stopped caching new content once the disk cache was full, causing pages and resources to be re-downloaded from the network on every visit. (Bug 2031577)
- Fixed an issue where some websites could render incorrectly or fail to load when they used JavaScript to insert WebKit-specific style rules. (Bug 2040693)
- Fixed an issue where clicking and selecting text in some input fields and text areas did not work on pages that styled them with certain CSS rules. (Bug 2039504)
- Fixed an issue where the up and down buttons on number input fields could overlap and hide the value when sites sized the field to fit its contents. (Bug 2039315)
- Fixed an issue where sorting strings that include numbers could produce an incorrect order on some websites and web applications. (Bug 2027078)
- Fixed an issue where dropdown menus would not open for <select> elements created inside an iframe and then moved into the parent page. (Bug 2041720)
- Reference link to 151.0.1 release notes.

Version 151.0.1, first offered to Release channel users on May 21, 2026

Fixed
- Fixed a crash experienced by users with Intel Raptor Lake CPUs. (Bug 1950764)
- Fixed an issue on Windows where some websites using WebSerial to flash device firmware could fail unexpectedly. (Bug 2040754)
- Reference link to 151.0 release notes.

Version 151.0, first offered to Release channel users on May 19, 2026

New
- Firefox Home (New Tab) has a fresh, new look and feel. The layout and design will enable upcoming features, from widgets to shortcuts improvements, launching between 151 and 152. Included are some new and exciting Wallpapers, such as the one below. Use the pencil icon in the lower right to check them out.

- Private Browsing Mode now allows you to instantly clear all data from your current session without closing the entire window. When you select the End Private Session button (the fire icon) to the right of the URL bar, Firefox will ask you to confirm to clear your session. Once confirmed, it will wipe all of your private browsing data and open a fresh new Private Browsing Mode session for you.

- Firefox now strengthens protection against fingerprinting in Standard Enhanced Tracking Protection, making it harder for websites to track you across sites by limiting the amount of information revealed about your device and browser. This reduces the number of users uniquely identifiable by common fingerprinting techniques by an average of ~14%, and by ~49% on macOS.
- You can now merge multiple PDFs directly in the Firefox PDF viewer.

- The Translations page (about:translations) is now accessible through the More Tools section of the Application Menu.
- Local Firefox profile backups are now available on Linux in addition to Windows, and you can restore them across platforms.
- On macOS, URLs copied from iOS devices using Apple’s Universal Clipboard now paste correctly in Firefox.
- On macOS, dropdown menus on web pages now use the native macOS menu style, matching the look and behavior of the rest of the system.
- Address Autofill is enabled for users in the Netherlands.

Fixed
- Fixed incorrect screen resolution reporting to websites in multi-monitor setups.
- Fixed an issue on macOS where maximized Firefox windows could reopen on the wrong monitor after relaunching in multi-monitor setups.
- Improved color management for copied and pasted images on macOS.
- Various security fixes.

Changed
- The search bar in Firefox Settings (about:preferences) is now larger and spans the full width of the settings content area, making it easier to find options.
- Extensions and Themes installed in a Firefox Desktop profile directory will be restored successfully after the profile directory is moved or restored to a different location or a different operating system.
- Geolocation on Windows now respects the user's Windows location permission setting, instead of overriding it, when the user grants location permission to a page. Firefox will ask users to enable the Windows permission if it is needed.

Enterprise
- You can find information about policy updates and enterprise-specific bug fixes in the Firefox for Enterprise 151 Release Notes.

Developer

Web Platform
- You can now manage microcontrollers that support serial communications in Firefox via the Web Serial API. This lets you program microcontrollers and development boards, such as ESP devices, Raspberry Pi Picos, 3D printers, CNC machines, and other devices. Web Serial can be used in Extensions, but not from moz-extension contexts at this time.
- Local network access restrictions are now rolling out to all users. Firefox requires websites to request permission before connecting to devices on your local network or to apps and services on your device. Previously, this protection was limited to users with Enhanced Tracking Protection set to Strict.
This feature is part of a progressive roll out.
What is a progressive roll out?
Certain new Firefox features are released gradually. This means some users will see the feature before everyone does. This approach helps to get early feedback to catch bugs and improve behavior quickly, meaning more Firefox users overall have a better experience.
- The new Fullscreen Keyboard Lock API adds an optional argument to requestFullscreen that allows websites to request that whil

We’re still preparing the notes for this release, and will post them here when they are ready. Please check back later.

We’re still preparing the notes for this release, and will post them here when they are ready. Please check back later.

We’re still preparing the notes for this release, and will post them here when they are ready. Please check back later.

Version 150.0, first offered to Release channel users on April 21, 2026

New
- Split View just got better: You can now right-click any link and choose Open Link in Split View to open it alongside your current tab. You can also search open tabs when creating a split view and quickly reverse tab positions using the new Reverse Tabs option in the tab context menu.
- Share multiple tabs in a single step: select several tabs, right-click, and choose Share → Copy X links. When pasted into other apps, links include both the page title and URL for easy reading.
- You can now use Firefox’s built-in PDF editor to reorder, copy, paste, delete, and export pages in a PDF.
- Local network access restrictions are now being extended to all users. Firefox will require websites to request your permission before connecting to devices on your local network or to apps and services on your device. Previously limited to users with Enhanced Tracking Protection set to Strict, this protection is now rolling out gradually to all users. You can find more details about this on our support page.
- Try out real-time, private translations in Firefox Desktop with the about:translations page. Start typing the word "translate" into the URL bar for a quick-action shortcut to the page.

- Added support for the GTK emoji picker on Linux, allowing users to insert emoji using the system shortcut (typically Ctrl+.).
- Firefox web apps are now available to Windows users who installed Firefox through the Microsoft Store.
- The new Firefox Profile management system is now available to all users, including users on Windows 10.
- Backing up a profile to a file is now available to all Windows 10 and 11 users, including those who use the new profile management system.
- Firefox now ships with a new .rpm package for Linux users on Red Hat, Fedora, openSUSE, and other RPM-based distributions.

Fixed
- Fixed an issue on macOS where, when macOS Lockdown mode is enabled, emoji characters are not displayed in web content.
- Various security fixes.

Changed
- If you prefer creating tab groups from the context menu, you can now turn off drag-and-drop group creation in Settings > Tabs > Drag tabs to create tab groups.

Enterprise
- You can find information about policy updates and enterprise-specific bug fixes in the Firefox for Enterprise 150 Release Notes.

Developer
- A new element-specific section has been added to the pseudo-class toggle panel including a toggle for the :open pseudo-class, which is only available for elements that have an open state like <dialog> elements. The existing toggle for the :visited pseudo-class was also moved there, as it only applies to <a> and <area> elements. (Learn More)
- The Document.caretPositionFromPoint() method now only returns a position in a shadow DOM if its ShadowRoot is passed in the newly-added shadowRoots option.
- The devtools network monitor now indicates when a connection used a certificate issued by a certificate authority not in Mozilla's Root CA Program.

Web Platform
- Firefox now supports the ariaNotify API for accessibility notifications (e.g. for screen readers) as a more ergonomic and reliable alternative to ARIA live regions.
- Firefox now supports media element pseudo-classes (e.g., :playing, :paused) to allow more precise styling based on media playback state.
- Added support for the highlightsFromPoint() API, which allows web pages to interact with CSS Highlights by returning all Highlights at a given point.
- Firefox now supports light-dark() on images, just like on colors, which is very useful for supporting dark mode on websites.
- The color-mix() function previously accepted only two color values. This limitation has now been removed, allowing the function to accept an arbitrary number of colors.
- Added support for a new auto value on the sizes attribute for lazy-loaded image elements with multiple images defined via srcset. This allows the browser to automatically select the right image based on the layout width 

Version 149.0.2, first offered to Release channel users on April 7, 2026

Fixed
- Various security fixes.
- Fixed an issue where certain parts of web pages, such as drop-down menus and specific styles, did not appear correctly when printing. (Bug 2026109)
- Fixed an issue where some website error pages displayed generic connection messages instead of the specific error code and description provided by the server. (Bug 2023800)
- Fixed a crash that occurred when using certain security keys or WebAuthn features for two-factor authentication. (Bug 2026688)
- Fixed an issue on Linux where the browser toolbar could become unresponsive to mouse clicks after dragging a tab when using Wayland. (Bug 2022238)
- Fixed a layout issue where text inside certain graphics (SVG) appeared shifted or misaligned from its intended position. (Bug 2024647)
- Fixed an issue where the "Send to device" option failed to work when used from the Open Tabs section in Firefox View. (Bug 2023201)

Enterprise
- Introduced a new enterprise policy that allows administrators to directly manage and control AI-related features within Firefox. (Bug 2019983)
- Fixed an issue where enterprise policies for the browser homepage and start page were not being applied correctly. (Bug 2027888)
- Introduced a new enterprise policy that allows administrators to prevent the built-in VPN and IP protection features from being available to users. (Bug 2022365)
- Reference link to 149.0 release notes.

Version 149.0, first offered to Release channel users on March 24, 2026

New
- View two pages side-by-side in a single window with the new Split View feature that makes it easier to compare information, research topics or work across two pages at once. To create a split view, select one or two tabs and choose Add to Split View or Open in Split View.

- Firefox now offers a free built-in VPN. Whether you’re using public Wi-Fi while traveling, searching for sensitive health information, or shopping for something personal, this feature gives you a simple way to stay protected. Once you sign in and turn it on, you can hide your location and IP address by routing it through a secure proxy while you browse in Firefox. You will get 50 GB of protection every month, with the option to turn it on or off for specific websites. This feature is progressively rolling out in the US, UK, Germany and France starting today.

This feature is part of a progressive roll out.
What is a progressive roll out?
Certain new Firefox features are released gradually. This means some users will see the feature before everyone does. This approach helps to get early feedback to catch bugs and improve behavior quickly, meaning more Firefox users overall have a better experience.
- Many PDF files will now load significantly faster thanks to hardware acceleration.
- Firefox now automatically blocks notifications and permanently revokes permissions for any website flagged as malicious by SafeBrowsing. This prevents unsafe sites from sending background notifications to users, commonly used for ads, spam or phishing.
- You can now add a Share button to your toolbar via Customize Toolbar, making it easy to share the current tab using your Windows or macOS system sharing options.
- Address Autofill is enabled for users in Australia, India, Italy, Poland and Austria.
- Explore more of the web with new on-device translation support for Bosnian, Norwegian Bokmål, Serbian and Thai — plus improved accuracy for Croatian.

Firefox Labs
- Tab notes feature that lets you attach a short note to a web page is now available in Firefox Labs. You can use notes to remember why you opened a page, what you planned to do next or any details you want to revisit later. Please give notes a try and share your feedback on what works well and what can be improved.

Fixed
- Increased robustness of HTTP/3 upload performance for unstable network conditions.
- Various security fixes.

Changed
- The TrustPanel combines the privacy and security panels accessed from the address bar to give the user one place to check the Privacy and Security settings of the current page. Learn more.

- Security has been strengthened by tightening the requirements for JavaScript files that can be loaded in the parent process, providing additional defense in depth against potential threats.
- On Linux, Firefox will now default to the XDG portal file picker if available, rather than the GTK3 one, which is usually better integrated with the user's desktop environment, and more powerful.
- Firefox error pages have a fresh new look, with updated visuals that better match the overall feel of Firefox. The redesigned pages create a more cohesive experience while making it clearer what went wrong.

- On Windows, Firefox will use the modern Windows.Devices.Geolocation API for geolocation instead of Windows 7 location API.

Developer
- The toolbar of the Storage Inspector now has a button to delete all entries of the currently selected storage.
- Besides each CSS declaration related to a computed value shown in the Computed view there's now an icon to jump to it in the Rules view.

Web Platform
- showPicker() now supports text-based <input> elements with an associated <datalist>, displaying the autofill dropdown. See documentation.
- The functions xywh() and rect() were previously implemented for the clip-path and offset-path properties. They are now also available for the shape-outside property.
- The math value of the CSS f

Version 148.0.2, first offered to Release channel users on March 10, 2026

Fixed
- Fixed an issue where searches entered in the Firefox Home search field were incorrectly redirected to the address bar for some users who had disabled search handoff behavior via advanced settings. (Bug 2017049)
- Fixed an issue where some web-based rich text editors stopped applying formatting, such as bold or italic. (Bug 2020927)
- Fixed an issue where videos could autoplay unexpectedly on YouTube despite autoplay being blocked, particularly impacting screen reader users. (Bug 2020233)
- Fixed an issue that caused some absolutely positioned elements meant to be centered, for example, using margin: auto with inset: 0, to appear left-aligned on initial load. (Bug 2017440)
- Fixed an issue where the “Switch to Tab” suggestion in the address bar appeared blank for pages without a title. (Bug 2020341)
- Fixed an issue that could reduce video quality on Windows systems using NVIDIA GPUs with Video Super Resolution enabled. (Bug 2019515)
- Various security fixes.
- Reference link to 148.0 release notes.

New
- Interoperability improvements for the CSS anchor positioning and Navigation web APIs.
Fixed
- Fixed a regression where position: sticky elements on some webpages could appear stuck or fail to update while mousewheel-scrolling after certain :hover interactions. (Bug 2010481)
- Fixed an issue where the Firefox Developer Tools could fail to re-open after using the Inspector’s node picker and reloading a page containing cross-origin iframes. (Bug 2003810)
- Fixed an issue where the DNS over HTTPS provider settings section could appear as a blank box, preventing users from seeing the current setting or changing it. (Bug 2010501)
- Fixed an issue on Windows systems with a large number of fonts installed where parts of the Firefox UI (tabs, menus, and Settings) could display garbled characters or symbols instead of readable text. (Bug 2012950)
- Reference link to 147.0.2 release notes.
Unresolved
- On Linux (Wayland) systems, certain popups and context menus will sometimes open in the wrong place, such as the top-left corner of the window. Firefox 147.0.3 has a partial mitigation for this problem and remaining instances will be addressed in a future release. (Bug 2003045)

New
- Firefox now allows you to customize your keyboard shortcuts to replace hard-to-type or hard-to-remember hotkeys, eliminate conflicts with other software, and create your preferred set. Access this experimental new feature by typing about:keyboard in the address bar.
Fixed
- Resolved various issues with missing or impaired browser functionality when using XDG Base Directories on Linux. (Bug 2011300)
- Fixed an issue causing excess passkey prompts to appear when logging into some sites. (Bug 2010919)
- Fixed an issue that could lead to sites being incorrectly flagged as malicious by SafeBrowsing. (Bug 2010956)
- Various security fixes.
- Reference link to 147.0.1 release notes.

Fixed
- Fixed compatibility problems with websites that use the new Compression Dictionaries technology, such as ChatGPT, by temporarily disabling the feature. (Bug 2010712)
- Fixed an issue where an unnecessary empty directory was created on Linux systems. (Bug 2001887)
- Fixed an issue where time formats could cause certain websites to display incorrectly. (Bug 2010411)
- Reference link to 147.0 release notes.

New
- WebGPU support is now enabled for devices with Apple Silicon processors on all supported macOS versions.
- Improved video playback performance on systems with AMD GPUs by enabling zero-copy playback for hardware-decoded video where supported, bringing them to parity with Intel and NVIDIA GPUs.
- Firefox now supports the Safe Browsing V5 protocol and is migrating from Safe Browsing V4 to the local list mode of Safe Browsing V5 protocol.
- Users with Enhanced Tracking Protection (ETP) set to Strict will have local network access restrictions enabled by default. Firefox will now require users to explicitly allow public websites to access local network resources.
This feature is part of a progressive roll out.
What is a progressive roll out?
Certain new Firefox features are released gradually. This means some users will see the feature before everyone does. This approach helps to get early feedback to catch bugs and improve behavior quickly, meaning more Firefox users overall have a better experience.
- Firefox now supports the Freedesktop.org XDG Base Directory Specification.
- A Picture-in-Picture player window can now optionally be opened automatically for a video playing in a tab when that tab goes into the background. A special thanks to volunteer Daniele Ferla for contributing this feature!

Fixed
- Fixed an issue that prevented some Windows users from selecting a tab when the cursor was at the top of the screen and the Firefox window was maximized.
- Fixed a bug that made HTTP/3 requests containing non-UTF-8 header values time out or fall back to HTTP/2 after a while.
- A draggable button can now be dragged if initiated from the button itself.
- For Linux GNOME Mutter users, window and rendering surface sizes were updated to match the actual pixel grid so Firefox delivers sharp rendering on fractionally scaled displays regardless of the actual window size.
- Various security fixes.
Changed
- Firefox now uses the same quality values (q-values) in Accept-Language headers as other major browsers. The second language preference is now sent as q=0.9 instead of q=0.5, with subsequent language preferences decreasing by 0.1 each (minimum 0.1). This change fixes compatibility issues with some servers that incorrectly rejected requests with lower quality values.
Enterprise
- You can find information about policy updates and enterprise-specific bug fixes in the Firefox for Enterprise 147 Release Notes.
Developer
- View Transitions: View transition pseudo-elements now appear in the elements panel and the associated animations appear in the animations panel.
- Anchor positioning: Elements with a valid anchor-name are given an 'anchor' badge in the elements view, and @position-try CSS rules are now displayed in the CSS rules panel when an element using position-try-fallbacks is selected.
- The JSON viewer now has a button to import the resource into Firefox Profiler to get a breakdown of its size.
- Pseudo-element selectors can now be added/edited in the CSS rules panel.
Web Platform
- Added support for the Navigation API. This API provides the ability to initiate, intercept, and manage browser navigation actions. It is a successor to previous web platform features such as the History API and window.location, which solves their shortcomings.
- The Unicode ICU library was updated to release 78, bringing support for Unicode 17 and new locales.
- ES modules in service workers are now supported, aligning Firefox with other major browsers and improving compatibility for modern web apps.
- Support for CSS Module Scripts was added, allowing stylesheets to be imported using the JavaScript module system and import attributes.
- The CSS counter-* and quotes properties are now supported in the ::marker pseudo-element.
- Both CompressionStream and DecompressionStream now support the Brotli format.
- Firefox now supports the :active-view-transition-type selector and associated View Transitions API changes.
- Firefox now exposes the view transit

Fixed
- Improved overall stability by fixing crashes related to browsing, graphics, and accessibility features. (Bugs 2001160, 1998185, 1998188)
- Fixed an issue where fingerprinting protection caused incorrect font rendering on popular websites. (Bug 2000429)
- Fixed crashes related to media playback and GMP process shutdown. (Bug 2002697)
- Fixed an issue where desktop profile shortcuts were being unintentionally removed when changing copied profile settings. (Bug 1998209)
- Improved sidebar text contrast when using vertical tabs with certain themes. (Bug 2006091)
- When restoring from a backup, the restore success message will appear over the new tab page instead of one of the tabs restored from a backup, to avoid cases where the restored tab canceled the restore success message. (Bug 2003307)
- Various security fixes.
- Reference link to 146.0 release notes.
Unresolved
- On Windows, clicking tabs may not work at the very top of the screen when Firefox is maximized on a second monitor. We’re working to fix this in a future release. (Fixed in 147.0)

New
- Windows 10 users can now automatically protect their passwords, bookmarks, and more by turning on backup in Firefox. Your browsing data is saved daily on your device and can be encrypted with a password. When you set up a fresh install of Firefox on any operating system for a new device or your current one, you can restore from this backup and pick up right where you left off. This feature is currently available on Windows devices and will be coming to other operating systems soon.

This feature is part of a progressive roll out.
What is a progressive roll out?
Certain new Firefox features are released gradually. This means some users will see the feature before everyone does. This approach helps to get early feedback to catch bugs and improve behavior quickly, meaning more Firefox users overall have a better experience.
- MacOS users now have a dedicated GPU process by default. This includes WebGPU, WebGL, and Firefox's own WebRender. With this feature enabled, fatal errors in graphics code will no longer crash the browser, and will instead transparently restart the GPU process.
- Firefox Labs is now available to all users, regardless of whether they choose to participate in studies or submit telemetry. This means more experimental features are now available to more people.
- Users can now skip the results page and see direct results as they type in the search bar for faster, simpler browsing.

This feature is part of a progressive roll out.
What is a progressive roll out?
Certain new Firefox features are released gradually. This means some users will see the feature before everyone does. This approach helps to get early feedback to catch bugs and improve behavior quickly, meaning more Firefox users overall have a better experience.
- There is a New Tab Weather opt-in workflow available for users in the EU and some other countries, where they can choose whether to enable location detection or manually search for a location.

This feature is part of a progressive roll out.
What is a progressive roll out?
Certain new Firefox features are released gradually. This means some users will see the feature before everyone does. This approach helps to get early feedback to catch bugs and improve behavior quickly, meaning more Firefox users overall have a better experience.
- Firefox now natively supports fractional scaled displays on Linux (Wayland), making rendering more effective.
- For users of the English-language versions of Firefox in France, Germany, and Italy, the address bar now shows English-language suggestions for holidays and other important dates.
Fixed
- When the timepicker is enabled for <input type="time"> and <input type="datetime-local">, it now provides full keyboard and assistive technology support. This update also improves the behavior of the time spin buttons for users who prefer reduced motion. The Firefox Accessibility team hopes that making the built-in timepicker accessible will encourage wider adoption of browser-provided time and date inputs across the web, reducing the need for custom controls, and improving accessibility for all users.
- Various security fixes.
Changed
- The Colors dialog in Settings now uses clearer color picker controls that keep each color sample next to its label. It makes it easier to understand and adjust text, background, and link colors when using a forced colors palette to customize the default text, link, and page background colors, especially with or without screen magnifiers.

- Firefox removed support for Direct2D on Windows. If you still require Direct2D support, please use ESR 140.0 or higher.
Enterprise
- You can find information about policy updates and enterprise specific bug fixes in the Firefox for Enterprise 146 Release Notes.
Developer
- Firefox now supports ML-KEM for WebRTC, by sending a post-quantum (PQ) key share during the DTLS 1.3 handshake. ML-KEM is the next-generation public-key cryptosystem that is believed to be secure against attackers with large q

Fixed
- Fixed an issue that prevented typing in Baidu’s search box when using Chinese IMEs on Windows.(Bug 2000479)
- Reference link to 145.0.1 release notes.
Unresolved
- On Windows, clicking tabs may not work at the very top of the screen when Firefox is maximized on a second monitor. We’re working to fix this in a future release.

Fixed
- Fixed an issue causing breakage on sites using Three.js. (Bug 1995939)
- Fixed a failure to open Firefox from the desktop launcher on older versions of Windows 10. (Bug 2000411)
- Fixed Web compatibility issues with Rogers. Rogers customers would see a broken iframe with "Firefox Can’t Open This Page" when viewing bills, rather than the billing info. (Bug 1996823)
- Fixed an issue in the Web Developer Tools preventing copy all or save all requests as HAR. (Bug 1995694)
- Reference link to 145.0 release notes.

New
- Add, edit, and delete comments to make your own notes in PDFs (summaries, questions, tasks, etc.). The comment sidebar helps you scan all your comments and quickly jump to them, which is handy for long or heavily marked-up PDFs.

- This version introduces a new phase of privacy protections, building on our research on reducing browser fingerprinting. These new defenses cut the percentage of users seen as unique almost in half, ensuring a safer and more private browsing experience in Private Browsing or when using Enhanced Tracking Protection set to Strict.
- Need a reminder of what tabs are in a group? Hover over the tab group name to get a preview of the tabs inside without opening it.
- You can now access and manage your saved passwords right from the sidebar—no need to open a new tab or window. Stay on the page you’re on and get to your logins faster.

- Copy Link to Highlight allows users to share arbitrary sections of a page with others by copying a link through the context menu with a given selection
- The Translations feature has an improved experience when translating between languages with different script directions.
- New brand-inspired wallpapers are available for New Tab on desktop, with versions for both light and dark mode.
- With the new Open links from apps next to your active tab setting, you can have links from other applications open next to your active tab instead of at the end of the tab strip.

- Enhanced Bounce Tracking Protection’s stateless mode is now enabled by default in ETP Strict, blocking more advanced tracking techniques based on redirection
- For most Windows users, the existing desktop shortcut for launching Firefox has been replaced with the desktop launcher, a small program that will launch Firefox if it is installed, but if it is not installed will prompt the user to install Firefox. This will provide an easy installation point for Firefox users who acquire a new Windows device, where Firefox will not be installed by default, but the desktop launcher program may have synced via OneDrive or other cloud storage product. Learn more.

Fixed
- Various security fixes.
Changed
- Firefox no longer supports 32-bit Linux systems. We recommend installing the 64-bit version for continued updates and support.
- Horizontal tabs are now slightly more rounded to match the look of vertical tabs. Buttons and text inputs, including the address bar, have also been updated for consistency.
- When no extensions are installed, clicking the Extensions button now shows a message highlighting how extensions can enhance your browsing, with links to the Firefox Add-ons store.
- Local translation models are now compressed with Zstandard, reducing download sizes and on-device storage consumption. As always, all Firefox translations happen securely and privately on your local device, unlike other browsers that translate using cloud services.
- We updated default automation preferences to better support Agentic browsing, reducing the steps agents need to complete a task and chances for the agent to get stuck.
Enterprise
- You can find information about policy updates and enterprise specific bug fixes in the Firefox for Enterprise 145 Release Notes.
Developer
- Microsoft UI Automation phased release rollout at 100%. Microsoft UI Automation is the new accessibility framework for Microsoft Windows. This will provide better assistive technology (AT) support and performance on Windows for current and future assistive technologies.
Web Platform
- Support has been added for the Atomics.waitAsync proposal, which is a non-blocking, asynchronous version of Atomics.wait. This allow synchronization of threads based upon the value in a shared memory location, for more details please consult our MDN documentation.
- Firefox now supports the new Integrity-Policy header for enforcing sub-resource integrity for scripts. Further implementation of this header is underway. Further implementation of this header is underway.
- Added Mat

New
- Focus on just one tab in a group without the clutter. Your active tab now stays in view, keeping things tidy even with the group collapsed.

- We’re excited to share another tab groups update that addresses a top request from our community! You can now drag a tab into a collapsed group without automatically expanding it. It’s a quick way to stay organized while minimizing visual distractions.
- Profile management, now available to all users globally, helps protect your privacy and stay focused by separating your online life into distinct profiles — for work, school, vacation planning, or whatever you choose. You can now name your profiles and customize them with avatars and color themes for easy recognition, then quickly switch between them — all while keeping bookmarks, tabs, and browsing history completely separate.

- You can now close a Picture-in-Picture window without pausing the video. Press Shift + Click on the close button or use Shift + Esc to exit while keeping playback uninterrupted.
- Logins stored in the Firefox Password Manager are now encrypted on disk using a modern encryption scheme (AES-256-CBC), replacing the older 3DES-CBC. This change improves local data protection. Logins synced through Firefox Sync remain end-to-end encrypted and already use AES-256-GCM.
- Visual search powered by Google Lens
With just a right-click on any image, you can now:
✨ Find similar products, places, or objects
✨ Copy, translate, or search text from images
✨ Get inspiration for learning, travel, or shopping
Look for the new “Search Image with Google Lens” option in your right-click menu (highlighted with a NEW badge at first).
This is a desktop-only feature, available worldwide. Your default search engine must be set to Google in order to use it.

- Perplexity AI Search in Firefox
On desktop, Firefox now includes Perplexity, an AI-powered answer engine built into the browser. Perplexity delivers direct, conversational answers to complex questions, helping you get quick summaries, accurate references, or creative inspiration without digging through multiple sources. It’s available worldwide from the address bar via the unified search button.
- The following languages are now available for translation:
- Azerbaijani
- Bangla
- Icelandic
Fixed
- Various security fixes.
- The following languages have improved translation quality:
- Arabic
- Bulgarian
- Catalan
- Chinese (Simplified)
- Czech
- Dutch
- Estonian
- Finnish
- French
- German
- Hungarian
- Italian
- Japanese
- Portuguese
- Persian
- Spanish
- Ukrainian
Changed
- On Windows, when opening a link from another application, Firefox will only use a window on the current virtual desktop or open a new window if needed.
Enterprise
- You can find information about policy updates and enterprise specific bug fixes in the Firefox for Enterprise 144 Release Notes.
Developer
- You can now jump to a CSS custom property's definition from within the var() function in style rules.
- The events tooltip in the Inspector now shows a badge besides custom events, making it easier to differentiate them from built-in events.
Web Platform
- Firefox now supports the Element.moveBefore API.
- Firefox now supports math-shift compact.
- Firefox now supports PerformanceEventTiming.interactionId, allowing developers to group related input events. This enables support for the Interaction to Next Paint (INP) responsiveness metric.
- Firefox now supports the command and commandfor attributes.
- Firefox now supports the View Transitions API Level 1. The View Transitions API provides a mechanism for easily creating animated transitions between different website views.
- Dithering is now applied when linear-gradient, conic-gradient, and radial-gradient are rendered using hardware WebRender.
- Firefox now supports the upsert proposal. This adds getOrInsert and getOrInsertComputed methods to Map and WeakMap. These methods either return the value associated with a key, or insert a default value, and then re

Fixed
- Improved Firefox' connection fallback behavior to mitigate sporadic slow/failed loads on some Google sites on systems with certain third-party software installed. (Bug 1990699)
- Reference link to 143.0.3 release notes.

Fixed
- Adjusted the timing of the new drag-to-pin interaction cue for better reliability. (Bug 1989344)
- Fixed an issue that prevented some extensions from updating via the Add-ons Manager. (Bug 1984724)
- Fixed a regression that prevented Firefox View sections from collapsing/expanding as expected. (Bug 1989200)
- Addressed a WebExtensions storage issue that could cause Firefox to crash on startup with certain extensions installed. (Bug 1989840)
- Fixed an issue where opening an add-on's "Extension settings" from the post-install prompt could break the Customize tab and some keyboard shortcuts until restart. (Bug 1983869)
- Reduced long delays when loading certain websites while connected to networks that block UDP connections. (Bug 1980812)
- Various stability and security fixes.
- Reference link to 143.0.1 release notes.

Fixed
- Fixed a tab crash experienced by some users caused by DLL injection. (Bug 1872261)
- Reference link to 143.0 release notes.

New
- On Windows, Firefox now supports running websites as web apps pinned directly to the taskbar. These are sites that you can pin and run as simplified windows directly from the taskbar without losing access to your installed add-ons. This feature is not currently available for Firefox installs from the Microsoft Store.
- Tabs can now be pinned by dragging them to the start of the tab strip, making it easier to keep important sites within reach.

- Copilot from Microsoft can now be chosen as a chatbot to use in the sidebar for quick access without leaving your main view.
- When a site asks for camera access, it can now be previewed inside the permission dialog. This is especially helpful when switching between multiple cameras.

- The Firefox address bar can now show you important dates and events. This feature supports displaying events (e.g. “Mother’s Day”) in the United States, United Kingdom, Germany, France, and Italy regions.
- Firefox has expanded its Fingerprinting Protection by reporting constant values for several more attributes of user's computers.
- When downloading a file in Private Browsing mode, Firefox now asks whether to keep or delete it after that session ends. You can adjust this behavior in Settings.

- Firefox now supports Windows UI Automation, which improves support for accessibility tools such as Windows Voice Access, Text Cursor Indicator and Narrator.
This feature is part of a progressive roll out.
What is a progressive roll out?
Certain new Firefox features are released gradually. This means some users will see the feature before everyone does. This approach helps to get early feedback to catch bugs and improve behavior quickly, meaning more Firefox users overall have a better experience.
Fixed
- Various security fixes.
Enterprise
- You can find information about policy updates and enterprise specific bug fixes in the Firefox for Enterprise 143 Release Notes.
Developer
- Unchecking the Group Similar Messages setting now prevents successive similar messages from being grouped so that all messages are displayed in the output.
- Switching between unmodified and pretty printed sources in the debugger no longer opens a new tab for pretty printed content.
Web Platform
- Firefox now supports xHE-AAC audio playback on Windows 11 22H2+, macOS, and Android 9+.
- Firefox now uses an updated grid sizing algorithm to better align with the CSS Grid specification. Grid layouts that use percentage row sizes or grid items containing elements with aspect ratios (such as images) will now render correctly in more cases.
- <input type=color> now recognizes the CSS <color> format in addition to the color hex format (#ffffff). This means that color names like black and more complex strings like rgb(200 200 200) are now valid inputs. For now the value will always be converted to the hex format.
- Restrictions were removed that prevented setting the display property on <details> elements, and a ::details-content pseudo-element was added to style the expandable/collapsible contents of those elements.
Community Contributions
- With the release of Firefox 143, we are pleased to welcome the developers who contributed their first code change to Firefox in this release, 12 of whom were brand new volunteers! Please join us in thanking each of these diligent and enthusiastic individuals, and take a look at their contributions:
- AnonAlly: 1978245
- Balraj Dhawan: 1977903
- Damia Vergnet: 1932365, 1979629
- Gaétan Fine: 1177108
- jonas.muecke: 1978226
- Markus Probst: 1976974
- Mason Abbruzzese: 1957214
- Mauro V [:cheff]: 1507381, 1849937, 1872780, 1938638, 1943057, 1975093, 1976968
- Nicolas Auvray [:Itms]: 1982134
- overflowcat: 1978108
- Robert: 1980791
- s1m: 1964526

Fixed
- Dragging multiple non-adjacent tabs in horizontal tab strip mode now correctly moves them together as a group. (Bug 1982933)
- Dragging multiple tabs no longer causes toolbar unresponsiveness or visual glitches. (Bug 1984342)
- Fixed an issue where the text cursor appeared in the wrong location.. (Bug 1984045)
- Fixed a crash related to gamepad use, particularly on macOS. (Bug 1870379)
- Fixed an issue where the expand on hover feature in the sidebar would sometimes stop working. (Bug 1982129)
- Fixed a crash in KDE Plasma when using certain custom window decorations. (Bug 1984823)
- Reference link to 142.0 release notes.

New
- For users in the United States, article recommendations on your New Tab page are now grouped into topic sections like Sports, Food, and Entertainment to make stories more organized and easier to scan. You can also follow topics you’re interested in and block ones you’d prefer not to see, giving you more control over what shows up when you open a new tab.

This feature is part of a progressive roll out.
What is a progressive roll out?
Certain new Firefox features are released gradually. This means some users will see the feature before everyone does. This approach helps to get early feedback to catch bugs and improve behavior quickly, meaning more Firefox users overall have a better experience.
- You can now see what’s behind a link before visiting it with Link Previews. Long press a link (or right-click and choose Preview Link). Previews can optionally include AI-generated key points, which are processed on your device to protect your privacy.
Link Previews is gradually rolling out to ensure performance and quality and is now available in en-US, en-CA, en-GB, en-AU for users with more than 3 GB of available RAM.
This feature is part of a progressive roll out.
What is a progressive roll out?
Certain new Firefox features are released gradually. This means some users will see the feature before everyone does. This approach helps to get early feedback to catch bugs and improve behavior quickly, meaning more Firefox users overall have a better experience.
- On Windows, clicking a persistent notification when Firefox is closed or restarted will now properly open Firefox with the relevant webpage, instead of just opening the main page of the website.
- ETP Strict mode now supports a flexible exception list to fix broken site features caused by tracker blocking. Exceptions are split into baseline (core functionality) and convenience (extra features), letting users choose improved site compatibility without compromising key privacy protections.
- Keep an active tab visible in a collapsed tab group
Focus on just one tab in a group without the clutter. Your active tab stays in view, keeping things tidy even with the group collapsed.
- You can now remove extensions from the sidebar by right-clicking the extension icon and selecting Remove from Sidebar.
Fixed
- Improved the scroll speed in the bookmarks dialog to not go beyond the component area.
- Improved drag-and-drop support for blob images.
- Various security fixes.
Changed
- Improved search results from browsing history via the address bar, reducing the likelihood of duplicate results being shown.
- Improved Netmonitor so that Request Headers/Cookies/Params are displayed in the Network panel even if the request isn't finished yet.
Enterprise
- You can find information about policy updates and enterprise-specific bug fixes in the Firefox for Enterprise 142 Release Notes.
Developer
- Firefox now supports the wllama API for extensions, enabling developers to integrate local language model (LLM) capabilities directly into their add-ons.
- The Debugger now offers a new setting to control whether the debugger overlay is shown during paused script execution.

- Firefox now supports the Prioritized Task Scheduling API, enabling developers to assign and manage task priorities.
- The Selection.getComposedRanges() API is now available, allowing developers to accurately get selected text ranges across shadow DOM boundaries.
- Added support for the URLPattern API, enabling developers to match and parse URLs using a standardized pattern syntax.
Community Contributions
- With the release of Firefox 142, we are pleased to welcome the developers who contributed their first code change to Firefox in this release, 20 of whom were brand new volunteers! Please join us in thanking each of these diligent and enthusiastic individuals, and take a look at their contributions:
- Alex Stout: 1845523
- Ayush Kaintura: 1963306
- Beatriz Rizental: 1971306, 1972755
- biyul.dev: 1931528, 1975074, 1976504
- cel

Fixed
- Fixed a regression that caused issues on sites built with the Svelte framework. (Bug 1980081)
- Fixed an issue where cryptominers were not listed as blocked in Strict Tracking Protection. (Bug 1977066)
- Reference link to 141.0.2 release notes.

Fixed
- Fixed a startup crash experienced by some Linux users with outdated NVIDIA drivers. (Bug 1978911)
- Fixed a regression that caused canvas objects to be draggable, causing web compatibility issues. (Bug 1978673)
- Fixed a crash in the Web Developer Tools panel that could occur when inspecting pages with <iframe> elements. (Bug 1975277)
- Fixed minor visual issues across the user interface. (Bug 1974269 · Bug 1976031 · Bug 1974876 · Bug 1976701)
- Firefox failed to start with GTK+ built without Wayland support in uncommon setups. (Bug 1978620)
- Fixed an issue where clicking a pinned tab could steal focus from the content area, disrupting keyboard navigation. (Bug 1977005)
- Reference link to 141.0 release notes.

New
- Now Firefox can help you keep your tabs organized, automatically. A local AI model identifies similar tabs, automatically organizes them into groups, and even suggests group names. Everything happens on your device to respect your privacy. Learn more here.

This feature is part of a progressive roll out.
What is a progressive roll out?
Certain new Firefox features are released gradually. This means some users will see the feature before everyone does. This approach helps to get early feedback to catch bugs and improve behavior quickly, meaning more Firefox users overall have a better experience.
- Vertical tabs users can now adjust the size of the tools areas at the bottom of the sidebar. To see fewer tools and more tabs, drag down the divider line which pushes extra tools into an overflow menu.

- On Linux, Firefox uses less memory and no longer requires a forced restart after an update has been applied by a package manager.
- Address autofill has been enabled for users in Brazil, Spain and Japan.
- The Firefox address bar can now be used as a unit converter. The unit converter supports converting units of length, temperature, mass, force, and angular measurement, as well as timezones (e.g. “now in GMT” , “10am EDT to CET”). Selecting the result will copy it to your clipboard.

- Firefox builds in Valencian now come with a built-in Catalan (Valencian variant) dictionary for the Firefox spellchecker.
- The following languages are now available for translation:
- Albanian
- Gujarati
- Hebrew
- Hindi
- Kannada
- Malay
- Malayalam
- Persian
- Telugu
Fixed
- Various security fixes.
Changed
- Firefox on Windows 11 now uses system provided font icons for the caption buttons, more in line with Windows 11 conventions.
Enterprise
- You can find information about policy updates and enterprise specific bug fixes in the Firefox for Enterprise 141 Release Notes.
Developer
- Firefox will now also clear the back-forward-cache when receiving the Clear-Site-Data: "cache" response header.
Web Platform
- Enabled the WebGPU API (spec; MDN) on Windows. For details, see the Mozilla Graphics Team Blog.
- Implemented the closedby attribute and it's related closedBy property on dialogs indicating the types of user actions that can be used to close the associated <dialog> element.
- Support for Cookies Having Independent Partitioned State (CHIPS) is now re-enabled, allowing developers to opt a cookie into storage partitioning per top-level site.
- The HTMLElement.showPopover() and HTMLElement.togglePopover() methods now take an options.source argument referencing the popover invoker, and togglePopover() also takes a force resp. options.force argument to force the popover open or closed.
Community Contributions
- With the release of Firefox 141, we are pleased to welcome the developers who contributed their first code change to Firefox in this release, 12 of whom were brand new volunteers! Please join us in thanking each of these diligent and enthusiastic individuals, and take a look at their contributions:
- ales.astone: 1920385, 1968910
- Chris Vander Linden: 1888847
- Gabriel Astorgano[:astor}: 1911190
- Jelte Fennema: 1945951
- Mr. Beedell, Roke Julian Lockhart (RJLB): 1969599
- Nick Crast: 1965895
- Sajid Anwar [:sajidanwar]: 825197, 1969770
- Simon Wülker: 1971080
- Skye Green [:skyevg]: 1965646
- viet-hung.nhu: 1968288
- wilsu: 1956211
- наб: 1970690

Fixed
- Fixed incorrect font selection in some cases when attempting to use color fonts. (Bug 1971053)
- Fixed the search results not updating when switching source during a file search in the Developer Tool's debugger. (Bug 1971094)
- Reference link to 140.0.2 release notes.

Fixed
- Fixed a startup crash on Windows experienced by some users. (Bug 1974259)
- Reference link to 140.0.1 release notes.

Fixed
- Fixed text contrast issues in the sidebar with some dark themes. (Bug 1971487)
- Fixed a startup crash experienced by some users caused by DLL injection. (Bug 1973947)
- Reference link to 140.0 release notes.

New
- Vertical Tabs: You can now keep more — or fewer — pinned tabs in view for quicker access to important windows. Just drag the divider to resize your pinned tabs section.

- Custom Search Engines: Firefox now supports adding even more search engines. To add a custom engine, right-click a search field of a supported website and select “Add Search Engine”, or go to Settings > Search > Add (below the search shortcuts table) to manually enter a search URL.
- Firefox Extensions: Customize your toolbar with the option to remove the extensions shortcut, giving you more control over your browser. When the button is hidden, you can access the extensions panel again at any time from the Firefox menu by clicking the Extensions menu item.
- You can now unload tabs by right-clicking on a tab (or multiple selected tabs) and selecting "Unload Tab". This can speed up performance by reducing Firefox's memory and CPU usage.
- Full-Page Translations now prioritizes translating only the content near your current view, improving speed and responsiveness. Content outside your view is skipped unless you scroll to it, reducing unnecessary resource usage.
- Firefox builds in Arabic now come with a built-in Arabic dictionary for the Firefox spellchecker.
- Address autofill enabled for users in Italy, Poland, and Austria.
Fixed
- Various security fixes.
Changed
- The Pocket toolbar icon, as well as the Pocket integrations on New Tab, have been removed per the service shutdown announcement.
Enterprise
- You can find information about policy updates and enterprise specific bug fixes in the Firefox for Enterprise 140 Release Notes.
Developer
- Improved the search feature in the Inspector panel to help developers more effectively search the DOM of the current page. Sorting the results by the number of matching elements, support “pseudo” selector state, etc.
Web Platform
- Added platform support for aria-keyshortcuts in Linux, macOS, and Windows.
- Added support for the CookieStore API, an asynchronous cookie API for scripts running in HTML documents and service workers.
- Added support for the Custom Highlight API, which allows styling arbitrary text ranges. Support for text-decoration is not included and is planned for an upcoming release.
- Added support for the pointerrawupdate event. This event provides lower-latency access to pointer movements by firing as soon as the pointer data is available, typically before the main pointermove event. Unlike pointermove, it performs an additional hit test to determine the target and fires more frequently, which may impact performance even if only a listener is added. This event is intended for applications that require high-precision input handling and cannot achieve smooth interaction using coalesced pointermove events alone.
- Service Workers are now available in Private Browsing Mode. This enhancement builds on our efforts to support IndexedDB and the DOM Cache API in Private Browsing through encrypted storage. With this change, more websites, especially those that rely on background tasks, will be able to benefit from Service workers.
- Firefox now applies a uniform user agent (UA) style to <h1> elements, regardless of whether they are used inside <article>, <aside>, <nav>, or <section>.
- Firefox will now escape less-than (<) and greater-than (>) symbols when serializing HTML attributes, making certain mXSS attacks on websites more difficult.
Community Contributions
- With the release of Firefox 140, we are pleased to welcome the developers who contributed their first code change to Firefox in this release, 18 of whom were brand new volunteers! Please join us in thanking each of these diligent and enthusiastic individuals, and take a look at their contributions:
- Abhishek Nimalan [:animalan]: 1895919
- jadavila9: 1852664
- Jilvin Jacob [:jilvin]: 1902439
- John McCann [:johnm]: 1952307
- Jörn Loviscach: 1906974
- Martin Pitt: 1947402, 1958325
- Matthias Riffard: 1964530
- Nathan Mentze:nmentz: 1951703, 19

Fixed
- Fixed Firefox freezing when switching between apps or opening certain panels within the browser. (Bug 1969253 & Bug 1969346)
- Fixed difficult selection of drop-down menu options in the Firefox preferences page when selected via the in-page search. (Bug 1968949)
- Fixed various selection issues when triple-clicking text in some situations. (Bug 1969100 & Bug 1969432)
- Fixed an incorrect filename being used when setting an image as the desktop wallpaper on Windows. (Bug 1969793)
- Various security fixes.
- Reference link to 139.0.1 release notes.

Fixed
- Fixed graphics corruption with certain NVIDIA graphics adapters and multiple monitors running at mixed refresh rates after updating to Firefox 139. (Bug 1968876)
- Reference link to 139.0 release notes.

New
- By popular request, Full-Page Translations are now available within Firefox extension pages that start with the moz-extension:// URL scheme.

- The New Tab custom wallpaper (and colors) option is now available! Your own image can be uploaded as your New Tab wallpaper or any custom color can be selected - from the brightest pink to dark gray. This feature will be rolling out gradually to new users and can also be enabled immediately via Firefox Labs. Additionally, new Wallpaper images and a new Celestial category have also been added.

- Link Previews is currently available as an experimental feature which can be enabled via Firefox Labs in the Firefox settings. After enabling, use the Alt+Shift keyboard shortcut when hovering over a link to see the previews in action!

Fixed
- PNG images with transparency now keep their transparency when pasted into Firefox.
- The upload performance of HTTP/3 has been significantly improved, particularly on resumed connections (QUIC 0-RTT) and high-bandwidth and high-delay connections.
- Various security fixes.
Changed
- Due to recent changes in how Chrome encrypts user data on Windows, the Firefox migration wizard can no longer directly import payment methods or passwords from Chrome. However, users can still export passwords from Chrome to a CSV file and then import them into Firefox using the migration wizard or the password manager.
- The Review Checker feature is shutting down and will no longer be available after June 10, 2025.
Enterprise
- You can find information about policy updates and enterprise specific bug fixes in the Firefox for Enterprise 139 Release Notes.
Developer
- Based on user requests from both Mozilla Connect and Stack Overflow, the filter setting in the Network panel is now preserved across DevTools Toolbox sessions.
- The Debugger's directory root is now scoped to the specific domain where it was set, which aligns with typical usage and avoids applying it across unrelated domains. This builds on previous improvements such as a redesigned UI and easier removal of the root setting. Setting a directory root updates the Source List to show only the selected directory and its children. Learn more
- The appearance of the paused line in the Debugger has been refined for better visibility, especially in high contrast mode.
Web Platform
- The Temporal proposal, a better version of Date, is now enabled by default in Firefox.
- Timer throttling for Workers is now supported.
- Closed <details> elements are now searchable and can be automatically expanded if found via find-in-page.
- Firefox now supports the hidden=until-found attribute, allowing content to be found via find-in-page when it's otherwise hidden by default.
- window.getSelection().toString() now correctly returns the text serialization when text is selected in a text control, improving cross-browser interoperability on some sites.
- Added support for the WebAuthn largeBlob extension.
- Added support for requestClose() to HTMLDialogElement.
- The built-in editor for contenteditable and designMode now handles collapsible white-space(s) before block boundaries and white-space sequences between visible content more consistently with Chrome. As a result, Gecko no longer inserts a padding <br> element after white-space before a block boundary, aligning behavior with other browsers.
Community Contributions
- With the release of Firefox 139, we are pleased to welcome the developers who contributed their first code change to Firefox in this release, 14 of whom were brand new volunteers! Please join us in thanking each of these diligent and enthusiastic individuals, and take a look at their contributions:
- adhaliwal34: 1888339
- Aidan Harris: 1960339
- Alexander Kuleshov: 1959970
- gene smith: 1891962
- giulianoverrando: 1930777
- Isaac Briandt: 1944944
- Jason Jones: 1176600, 1689254, 1855787, 1956009, 1960383
- Kanaru Sato [:canalun]: 1947061, 1958528, 1961558
- keanucuco: 1855839
- lucas.chollet: 1862235
- Raksha Kum

Fixed
- Security fixes.
- Reference link to 138.0.3 release notes.

Fixed
- Fixed a crash that could occur when viewing websites that use WebGL. (Bug 1961191)
- On Linux, fixed an issue where video playback would appear washed-out on Wayland when HDR support was unavailable. (Bug 1961610)
- Fixed an issue where the "Match Case" shortcut Alt+C in the find-in-page toolbar did not toggle the checkbox as expected. (Bug 1952611)
- Fixed an issue where the browser could repeatedly crash when certain SVG effects (like blur or drop shadow) were applied to very small areas. (Bug 1924241)
- Reference link to 138.0.1 release notes.

Fixed
- Fixed an issue which caused a blank page to be shown for Home and New Tab pages for some users. (Bug 1963537)
- Added a workaround for a bug in outlook.office.com/outlook.live.com where attachment filenames are incorrectly prefixed with UTF-8 when saved. (Bug 1961710)
- Reference link to 138.0 release notes.

New
- Profile management helps protect your privacy and stay focused by separating your online life into distinct profiles — for work, school, vacation planning, or whatever you choose. You can now name your profiles and customize them with avatars and color themes for easy recognition, then quickly switch between them — all while keeping bookmarks, tabs, and browsing history completely separate.

This feature is part of a progressive roll out.
What is a progressive roll out?
Certain new Firefox features are released gradually. This means some users will see the feature before everyone does. This approach helps to get early feedback to catch bugs and improve behavior quickly, meaning more Firefox users overall have a better experience.
- Users in the United States can now trigger weather suggestions in the address bar! Simply type a weather-related term or a city name, and view the result directly in the address bar dropdown.

Currently available in: United States
This feature is part of a progressive roll out.
What is a progressive roll out?
Certain new Firefox features are released gradually. This means some users will see the feature before everyone does. This approach helps to get early feedback to catch bugs and improve behavior quickly, meaning more Firefox users overall have a better experience.
- Tab Groups, a new way to organize and take control of your tabs, is now available to almost all users worldwide. You can create a group by dragging one tab onto another, pausing, then dropping it. You can also now reposition a tab group on the tab bar by dragging it.
- Firefox on Windows 11 now uses acrylic-style menus for popup windows, which better match the operating system’s aesthetic.
- You can now copy links from background tabs using the tabstrip context menu on MacOS and Linux.
Fixed
- Various security fixes.
Changed
- Improved the address and credit card autofill experience to better handle forms that update dynamically as users input information. Autofill now correctly fills newly revealed fields—such as those shown after selecting a country.
- Rededicated previous color settings to Contrast Control settings. (Learn more)
Enterprise
- You can find information about policy updates and enterprise specific bug fixes in the Firefox for Enterprise 138 Release Notes.
Developer
- Added support for the import map integrity field, allowing you to ensure the integrity of dynamically or statically imported modules.
- Implemented support for Error.isError, enabling brand checks to determine whether an object is an instance of Error. (Learn more)
- Added support for the error.captureStackTrace extension to improve compatibility with other browsers. (Learn more)
- A new column has been added to the Network panel to display the full path of the request URL. This enhancement makes helps developers quickly view and analyze complete request paths.
- Firefox now applies a uniform user agent (UA) style to <h1> elements, regardless of whether they are used inside <article>, <aside>, <nav>, or <section>. (Learn more)
This feature is part of a progressive roll out.
What is a progressive roll out?
Certain new Firefox features are released gradually. This means some users will see the feature before everyone does. This approach helps to get early feedback to catch bugs and improve behavior quickly, meaning more Firefox users overall have a better experience.
Web Platform
- Added support for Import Attributes, allowing developers to specify additional metadata when importing modules.
- Applications can now set their preferred degradation method to be used when the configured frame rate and resolution cannot be maintained. (Learn more)
- Firefox now enables the cache directive for the Clear-Site-Data header, allowing websites to clear the network cache. This gives websites more control over stored data, such as clearing the cache during logout to help mitigate privacy risks. (Learn more)
Unresolved
- Due to recent changes in Chrome on Windows,

Fixed
- Fixed file picker not being displayed when exporting passwords on macOS in about:logins for some users. (Bug 1956266)
- Fixed accessibility issues with the new PDF signature feature. (Bug 1956110 and Bug 1952571)
- Fixed an issue where using the context menu to paste in the Style Editor would insert the code twice. (Bug 1955854)
- Fixed functional regressions in our XSLT support introduced in 137. (Bug 1954841)
- Fixed a tooltip flickering issue on Windows that affected some users when hovering. (Bug 1958631)
- Fixed an issue where Firefox would not respond to clicks in some HTML5 video players. (Bug 1959251)
- Fixed an issue where radio inputs behaved incorrectly when preventDefault() was called on the click event. (Bug 1957956)
- Fixed an issue that caused some Firefox users to restart their browser multiple times to complete an update. (Bug 1959492)
- Security fix.
Changed
- Fixed an issue with DRM video playback on some sites caused by the general availability rollout of Microsoft's PlayReady hardware decryption DRM support in Firefox 137. PlayReady support is now limited to specific sites while broader compatibility continues to be tested. (Bug 1959827)
- Reference link to 137.0.1 release notes.
Unresolved
- Due to recent changes in Chrome on Windows, some users might find that the Firefox migration wizard no longer successfully imports passwords from Chrome or Chrome-based browsers. As a workaround, you can export your passwords as a CSV file from Chrome and then import them into Firefox using either the migration wizard or the Firefox password manager.