Firefox 126.0

The Copy Without Site Tracking option can now remove parameters from nested URLs. It also includes expanded support for blocking over 300 tracking parameters from copied links, including those from major shopping websites. Keep those trackers away when sharing links!

Firefox now supports Content-encoding: zstd (zstandard compression) . This is an alternative to broti and gzip compression for web content, and can provide higher compression levels for the same CPU used, or conversely lower server CPU use to get the same compression. This is heavily used on sites such as Facebook.

Catalan is now available in Firefox Translations.

Enabled AV1 hardware decode acceleration on macOS for M3 Macs.

Telemetry was added to create an aggregate count of searches by category to broadly inform search feature development. These categories are based on 20 high-level content types, such as "sports,” "business," and "travel". This data will not be associated with specific users and will be collected using OHTTP to remove IP addresses as potentially identifying metadata. No profiling will be performed, and no data will be shared with third parties. ( read more )

NVIDIA RTX Video Super Resolution (“VSR”) is now available in Firefox. RTX VSR enhances and sharpens lower resolution video when upscaled to higher resolutions and also removes blocky artifacts commonly visible on low bitrate streamed video. VSR requires at least a 20-series or higher NVIDIA RTX GPU, Microsoft Windows 10/11 64-bit, and NVIDIA driver version R530 or higher. The feature can be enabled in the NVIDIA control panel.

NVIDIA RTX Video HDR is now available in Firefox. RTX Video HDR automatically converts SDR video to vibrant HDR10 in real time, letting you enjoy video with improved clarity on your HDR10 panel. It requires at least a 20-series NVIDIA RTX GPU, Microsoft Windows 10/11 64-bit, and NVIDIA driver version 550 or higher. The feature can be enabled in the NVIDIA control panel.

The URL Paste Suggestion feature added in Fx125 was temporarily disabled while the team investigates a potential performance issue. The feature will be re-enabled in a future release once the performance issue is addressed.

On macOS, the text in the Crash Reporter dialog box is not localized for the non-en-US locales. This is tracked under Bug 1896097 and we will rollout a fix in a future release. (fixed in 126.0.1)

Various security fixes.

You can find information about policy updates and enterprise specific bug fixes in the Firefox for Enterprise 126 Release Notes .

Developer Information

Added an option to disable/enable the Developer Tools' split console feature.

With the release of Firefox 126, 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: [:flowejam]: 1885693

The commands.onCommand event now passes the tab argument to the event listener. This enables extensions to apply a triggered shortcut to the page in which it was issued, without the need to call the tabs.query() method ( Firefox bug 1843866 ).

The runtime.MessageSender type now includes the origin property. This enables message or connection requests to see the page or frame that opened the connection. This is useful for identifying if the origin can be trusted if it isn't apparent from the URL ( Firefox bug 1787379 ).

The "webRequestAuthProvider" permission is now supported. This provides compatibility with Chrome for requesting permission for webRequest.onAuthRequired in Manifest V3 ( Firefox bug 1820569 ).

The options_page manifest key is provided as an alias of the options_ui key. This has been provided to offer extensions better compatibility with Chrome ( Firefox bug 1816960 ).

The tabs.captureVisibleTab method is now also enabled by the activeTab permission , providing compatibility with Chrome and Safari ( Firefox bug 1784920 ).

Selections crossing shadow DOM boundary: dom.shadowdom.selection_across_boundary.enabled . The Selection.getComposedRanges() method can be used to get selection ranges that have anchor or focus nodes inside a shadow DOM — provided it is passed the ShadowRoot objects that contain those nodes. Selection methods setBaseAndExtent() , collapse() , and extend() have also been modified to accept nodes inside a shadow root ( Firefox bug 1867058 ).

CSS shape() function: layout.css.basic-shape-shape.enabled . You can use the shape() function to define shapes in the clip-path and offset-path properties. This function gives you more fine-grained control over the shapes you can define and offers several advantages over the path() function ( Firefox bug 1823463 for shape() function support in clip-path , Firefox bug 1884424 for shape() function support in offset-path , Firefox bug 1884425 for shape() interpolation support).

Implemented URL.parse() . Unlike the URL constructor , which throws when parsing fails, the static URL.parse() method returns null instead.

The CSS zoom property has been enabled by default following a lot of web compatibility and standardization work in the CSSWG.

Added support for CSS Custom :state() and CustomStateSet pseudo-classes.

Added support for Screen Wake Lock API .

Added support for IDBFactory.databases for enumeration of IndexedDB databases.

Added an option to disable split console ( Firefox bug 1731635 ).

The automatic adjustment for vertically centered operators (+, =, <, etc.) has been disabled by default. This behavior is not defined in MathML Core and was only necessary as a workaround for non-math fonts. It can still be enabled by setting the mathml.centered_operators.disabled config to false . ( Firefox bug 1890531 ).

The zoom property is now supported. It can be used to increase or decrease the size of an element and its contents ( Firefox bug 390936 ).

The zstd directive of the Content-Encoding HTTP header is now supported, allowing decoding of server-sent content encoded with the Zstandard compression algorithm ( Firefox bug 1871963 ).

IDBFactory.databases() is now supported for enumerating available IndexedDB API databases ( Firefox bug 934640 ).

IDBTransaction.durability can now be used for querying the transaction durability hint that the transaction was created with ( Firefox bug 1878143 ).

The URL.parse() static method is now supported for creating URL objects. This returns null if the passed parameters do not define a valid URL , and can hence be used as a non-throwing alternative to creating URL object with the URL constructor ( Firefox bug 1823354 ).

The Screen Wake Lock API is now supported, allowing a web application to request that the screen not be dimmed or locked while it is active. This is particularly useful for navigation and reading applications, as well as other applications where the screen may not receive regular tactile input when in use that would typically keep it awake. The API is accessed through Navigator.wakeLock in secure contexts, which returns a WakeLock . This allows you to request a WakeLockSentinel , which can be used to monitor the status of the wake lock and release it manually ( Firefox bug 1589554 , Firefox bug 1874849 ).

All RTCIceCandidate properties and methods are now supported and match the specification, with the exception of the unimplemented relayProtocol and url properties. The following changes were made to the properties of RTCIceCandidate :

The following properties were made read-only: candidate , sdpMid , sdpMLineIndex , and usernameFragment .

The following properties were added: foundation , component , priority , address , protocol , port , type , tcpType , relatedAddress , relatedPort , and usernameFragment .

The Element.currentCSSZoom read only property is now supported for getting the effective CSS zoom of an element ( Firefox bug 1880189 ).

The ability to define states for custom elements and match them using CSS selectors is now available by default. The custom states are represented as custom identifiers that can be added to or removed from the element's ElementInternals.states property (a CustomStateSet ). The CSS :state() pseudo-class takes a custom identifier as an argument and matches custom elements if the identifier is present in their set of states ( Firefox bug 1887543 ).

The Selection.direction property is now supported for indicating the direction of a range ( Firefox bug 1867058 ).

The <marquee> HTML element events bounce , finish , and start have been removed from HTMLMarqueeElement , along with the corresponding event handler attributes ( Firefox bug 1689705 ).

The Theora codec was disabled by default, and will be removed in a future release ( Firefox bug 1860492 ).

Added the contexts argument to the network.addIntercept command to limit the interception of network requests to particular top-level browsing contexts ( Firefox bug 1882260 ).

Both the commands session.subscribe and session.unsubscribe now raise an invalid argument error when the value of the arguments events or contexts are empty arrays ( Firefox bug 1887871 ).

Updated the implementation of the storage.getCookies command to align with the Gecko default cookie behavior. This allows the removal of the user value for the preference network.cookie.cookieBehavior , which was only expected to be set for our CDP implementation ( Firefox bug 1879503 ).

Removed the ownership and sandbox arguments for the browsingContext.locateNodes command because they are no longer necessary ( Firefox bug 1884935 ).

Improved error message for the session.new command when no capabilities are specified ( Firefox bug 1838152 ).