Firefox 142.0

What's new in this version:

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.
- 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
- 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:
- CVE-2025-9179: Sandbox escape due to invalid pointer in the Audio/Video: GMP component
- CVE-2025-9180: Same-origin policy bypass in the Graphics: Canvas2D component
- CVE-2025-9181: Uninitialized memory in the JavaScript Engine component
- CVE-2025-9182: Denial-of-service due to out-of-memory in the Graphics: WebRender component
- CVE-2025-9183: Spoofing issue in the Address Bar component
- CVE-2025-9187: Memory safety bugs fixed in Firefox 142 and Thunderbird 142
- CVE-2025-9184: Memory safety bugs fixed in Firefox ESR 140.2, Thunderbird ESR 140.2, Firefox 142 and Thunderbird 142
- CVE-2025-9185: Memory safety bugs fixed in Firefox ESR 115.27, Firefox ESR 128.14, Thunderbird ESR 128.14, Firefox ESR 140.2, Thunderbird ESR 140.2, Firefox 142 and Thunderbird 142

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:
Policies:
- The Permissions policy has been updated to allow you to configure permissions for screen sharing
- The EnableTrackingProtection policy has been updated to allow you to set the category to either strict or standard. When the category is set using this policy, the user cannot change it.
- The EnableTrackingProtection policy has been updated to allow you to set control Suspected fingerprinters. For more information

Special Notes:
- There is one more planned release of Firefox 128 ESR, and then it will go out of support on September 16, 2025. Users will then be automatically upgraded to Firefox 140 ESR.
- If you need to prevent upgrades for any reason, you can use the AppUpdatePin policy.

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