Fixed the Developer Tools eyedropper showing the wrong colors after the page is scrolled.
https://bugzilla.mozilla.org/1377755

Starting with Firefox 161, the address bar in Firefox Nightly explains why some results are shown, such as when a page was last visited or bookmarked.
https://bugzilla.mozilla.org/2086462

Browsing history imported from Chrome now includes how often you visited each page, so the sites you use most rank higher in address bar suggestions and shortcuts.
https://bugzilla.mozilla.org/1421485

Cross-document CSS view transitions are enabled on Firefox nightly
https://bugzilla.mozilla.org/2084340

Firefox Security & Privacy Newsletter 2026 Q3 | Attack & Defense
https://attackanddefense.dev/2026/11/02/firefox-security-and-privacy-newsletter-q3.html

Firefox now supports [nested arbitrary substitution functions][1] in the primary parameters of var(), attr(), and env(); for example, var(attr(data-theme-prop type(<custom-ident>))) and env(var(--safe-area-block-start)).
https://bugzilla.mozilla.org/2080511

Tab groups are now listed in the application menu, making it easier to find and reopen them
https://bugzilla.mozilla.org/2048790

Fixed typing with an input method, such as for Japanese or Korean, stopping after the first character in Canva Docs.
https://bugzilla.mozilla.org/2077043

Starting with Firefox 161, the search engine button in the address bar is always visible in Firefox Nightly, not only when the address bar is focused.
https://bugzilla.mozilla.org/2085310

Fixed some tabs not being restored after a restart when the saved session referred to a tab group that no longer existed.
https://bugzilla.mozilla.org/show_bug.cgi?id=2080608

Fixed WebRTC video calls with some services sending low-resolution H.264 video since Firefox 158.
https://bugzilla.mozilla.org/2082538

Fixed Firefox hanging on macOS 26+ when opening Spotlight with a large number of bookmarks.
https://bugzilla.mozilla.org/show_bug.cgi?id=2002102

Firefox now supports the random() CSS function, which allows authors to introduce randomness into their styles, generating a random value in a given range. https://developer.mozilla.org/docs/Web/CSS/Reference/Values/random

On macOS, keyboard shortcuts assigned to Firefox menu items in System Settings now replace the built-in shortcuts for those items.
https://bugzilla.mozilla.org/1333781

Fixed the Windows taskbar staying visible over fullscreen Firefox windows after switching back from another application.
https://bugzilla.mozilla.org/2085170

Firefox roadmap: What's new and what's coming next
https://blog.mozilla.org/en/firefox/firefox-roadmap/

Firefox now plays Matroska (MKV) files with FLAC, MP3, or PCM audio. 🎶
https://bugzilla.mozilla.org/1991747

You can now copy the current tab's URL with a keyboard shortcut. No shortcut is assigned by default, so you can choose your own key combination in about:keyboard (Ctrl+shift+C for example).

New nightly cycle started!

We're sad to hear Arc is sunsetting later this year. Their team put forth a lot of effort in prioritizing browser security, and their innovations influenced some of our own features, including Sidebar, Split View, and the upcoming Mini Window.

For those of you who are currently Arc users, what features do you want to see in your next browser?