148.0 Firefox Release
February 24, 2026
Version 148.0, first offered to Release channel users on February 24, 2026
Previous Firefox 147.0
New
Added an AI Controls section to Settings for managing AI-enhanced features. Learn more.
image for AI controls in Settings
Firefox now has improved support for screen readers accessing mathematical formulas embedded in PDFs.
Remote improvements are now decoupled from telemetry requirements in Firefox Settings. You can now opt into receiving remote browser changes even if you have opted out of sharing telemetry or participating in our experimental studies.
Firefox Backup is now available on Windows 10 to users who also use the “Clear history when Firefox closes” capability. Backups will not include any data which is set to be cleared when Firefox is closed.
The following languages are now available for translation:
Translation into and from Traditional Chinese.
Translation into Vietnamese.
New Tab wallpapers will now appear on new container tabs as well as new default tabs.
Fixed
Fixed an issue where a language pack could become disabled after a major update, causing Firefox to display in the wrong language.
On Windows, dragging a downloaded image to Adobe Illustrator now correctly inserts the image instead of its URL.
Various security fixes.
Developer
Developer Information
Web Platform
The initial about:blank document is now Web-compatible. If the first navigation of a browsing context goes to about:blank, it completes synchronously and is no longer replaced by a second parser-generated document.
Service worker support for WebGPU has been added, making it available in all worker contexts. Service workers allow WebGPU to run in the background, which is particularly useful for extensions and other pages that can meaningfully share resources across multiple tabs and time periods.
Firefox now supports the Iterator.zip() and Iterator.zipKeyed() methods from the joint iteration proposal. This allows zipping together underlying iterators into an iterator over values grouped by position, similar to zip in many other languages.
Firefox now supports the Trusted Types API, which is primarily aimed at preventing cross-site scripting attacks.
Firefox now supports the Sanitizer API, which provides new methods for HTML manipulation. The element.setHTML() method enables developers to insert HTML content similarly to element.innerHTML, but without the security vulnerabilities such as cross-site scripting (XSS). A complementary method, document.parseHTML(), is also available for parsing HTML safely.
Firefox now supports the location.ancestorOrigins attribute.
Firefox now supports the NavigationPrecommitController.addHandler() interface of the Navigation API. This allows registering a post-commit navigation handler during the pre-commit phase, to allow a multi-step navigation process.
Firefox now supports the position-try-order property as part of CSS Anchor Positioning, controlling the order of fallback positioning attempts.
Firefox now supports the CSS shape() function, which allows defining responsive free-form shapes in properties that take shapes like clip-path. Unlike path(), it uses standard CSS syntax, supports various CSS units, and allows mathematical functions.
