Following the release of Firefox 158, Mozilla promoted the next major release, Firefox 159, to the beta channel for public testing, so it’s time to take a look at the new features and improvements.
Firefox 159 promises easier access to saved passwords from the sidebar by default, the ability to search open tabs with a keyboard shortcut, support for importing bookmarks from Google Chrome profiles that are signed in to a Google account, and improved visuals for menus and panels on Linux and Windows.
Firefox 159 also promises to fix an issue with tabs sometimes detaching into a new window when clicked on Linux with Wayland, an issue with long drop-down lists on web pages showing a blank space in place of the last options, and loading issues with sites that reject an HTTP/3 request, falling back to HTTP/2 instead of failing.
On top of that, Firefox 159 promises to fix the file upload dialog opening in the last folder a file was saved to, such as Downloads, instead of the folder last used for uploads, as well as memory usage issues causing rapid growth when sites like the Zoom web app were left open in a minimized window.
Last but not least, Firefox 159 promises to display addresses written in the Balinese, Canadian Aboriginal Syllabics, Javanese, and N’Ko scripts in their own script instead of being encoded as “xn--” text, and updates the AI chatbot’s Summarize page option to share the page’s address instead of the page’s text content.
For macOS users, Firefox 159 promises support for the native macOS share picker, better support for web games when using a gamepad, support for opening the sign-in page for apps that sign in through the default browser, and better support for the Apple Writing Tools suite when pasting text on sites.
For Windows users, Firefox 159 promises to improve video playback when NVIDIA RTX Video HDR is enabled. Also, the upcoming Firefox release promises to update the Web Console to allow let, const, and class variables to be declared again, so a snippet can be edited and re-run without a redeclaration error.
For web developers, Firefox 159 promises support for scoped custom element registries, so custom elements that share a tag name can coexist on the same page, and support for scroll-driven animations, so CSS animations and Web Animations API animations can progress with the scroll position of a container.
In addition, it promises an updated Sanitizer API that can now sanitize HTML as it’s parsed rather than afterwards, so custom element constructors no longer run for elements the sanitizer removes. Also, WebGL now supports the EXT_clip_control and EXT_texture_mirror_clamp_to_edge extensions, and EXT_texture_norm16 for WebGL 2.
Mozilla plans to release Firefox 159 later this month, on October 27th, 2026, along with the Firefox 153.6 and Firefox 115.44.0 ESR releases. Until then, you can download the latest beta version of Firefox 159 right now from the official website, but keep in mind not to use it for production work.