Firefox 143.0

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.

Various security fixes .

You can find information about policy updates and enterprise specific bug fixes in the Firefox for Enterprise 143 Release Notes .

Developer Information

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.

When the Inspector is focused, the eyedropper can now be launched to pick a color via the Ctrl+Shift+Y keyboard shortcut.

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

Addition of storage.StorageArea.getKeys() . This method returns an array containing all of the keys in a storage area. It's available for all storage areas, that is sync , local , session , and managed . ( Firefox bug 1910669 )

User selection of an extension suggestion in the address bar (omnibox), an action that fires omnibox.onInputEntered , is now considered a user action . In addition to enabling the APIs that require a user action, selecting an extension suggestion in the address bar also grants the "activeTab" permission.

text-autospace : layout.css.text-autospace.enabled The text-autospace CSS property allows you to specify the space applied between Chinese/Japanese/Korean (CJK) and non-CJK characters. Currently these values are only parsed and there is no effect on the output. ( Firefox bug 1869577 ).

WebGPU external textures : dom.webgpu.external-texture.enable The GPUExternalTexture interface and GPUDevice.importExternalTexture() method are supported for importing external textures from video frames or elements. ( Firefox bug 1979100 ).

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.

The type="color" <input> element now accepts not only HEX colors like #ff6699 but also all CSS <color> values, for example oklab(50% 0.1 0.1 / 0.5) . ( Firefox bug 1965029 ).

The ::details-content pseudo-element is now enabled by default. It lets you style the content of the <details> element. ( Firefox bug 1941406 ).

The ::marker pseudo-element can now be used to style a list item that has been created using the ::before or the ::after pseudo-element. This is achieved using the ::before::marker and ::after::marker selectors. ( Firefox bug 1980215 ).

Multi-pass grid track sizing is now enabled by default and follows the algorithm outlined in the CSS Grid specification. In the multi-pass algorithm, columns are sized first, then rows; percentage values are resolved after the container size is known. With this default support, percentage-based row tracks and grid items with aspect ratios will now be sized correctly in more cases. ( Firefox bug 1957244 ).

The deprecated CompositionEvent.locale property is no longer supported. ( Firefox bug 1700969 ).

Updated the browsingContext.contextCreated event to be emitted for all open contexts when subscribing to the event ( Firefox bug 1754273 ).

Implemented new commands for the network module to enable recording network data:

network.addDataCollector adds a network data collector to contexts , userContexts or globally. The collector will record network data corresponding to the provided dataTypes . At the moment, only the "response" data type is supported. A maxEncodedDataSize must also be provided, network data exceeding this size will not be recorded ( Firefox bug 1971778 ).

network.removeDataCollector removes a previously added network data collector ( Firefox bug 1971781 ).

network.getData retrieves the data collected for a provided request id, dataType and optionally collector id. When providing a collector id, clients may also pass the disown flag to release the network data from the collector. Note that data is deleted when it is no longer owned by any collector ( Firefox bug 1971780 ).

network.disownData releases the data for a given request id and dataType from the provided collector id ( Firefox bug 1971779 ).

Fixed a bug where emulation.setLocaleOverride did not apply the override to newly created cross-origin iframes ( Firefox bug 1978533 ).

Fixed a bug where several commands such as session.subscribe would fail if any tab was unloaded ( Firefox bug 1949037 ).

Fixed the browsingContext.navigationCommitted event so that the url property now includes basic auth credentials. ( Firefox bug 1980137 ).