Mozilla shipped Firefox 159 on October 27, 2026, two weeks after Firefox 158, and the changelog reads like a shrug. No redesign, no new sidebar toy. That is exactly why Linux users should care: the two most annoying Firefox behaviors on a modern Linux desktop are fixed here, and both are the kind you only notice once they stop biting you.

The tab strip stops betraying you on Wayland

If you run Firefox on Wayland, and by now most desktop Linux users do, you may know this one by muscle memory. You click a tab to switch to it, and instead of switching, the tab tears off into its own window. You drag a tab upward to detach it on purpose, and nothing happens. Both directions of the same interaction were broken, in opposite ways, and both are fixed in Firefox 159.

A misclick that spawns a stray window breaks tiling layouts and scatters your session across workspaces. When the fix is this small and this central, update day is the day to re-test the gesture deliberately: click through your tabs, drag one upward to detach it on purpose, drag it back. If both work, the bug is gone for you.

The AMD memory leak on map pages is gone too

The second Linux fix targets a narrower but nastier problem. On systems with AMD graphics, Firefox could chew through excessive memory when viewing maps and place results, for example Mapbox-powered maps surfaced inside AI chat pages. The tab did not crash so much as swell, quietly, until the whole browser felt heavy.

Firefox 159 also fixes rapid memory growth from minimized web apps left open, the Zoom web app being the named example. After updating, the honest test is boring: open a map-heavy page, leave a web app minimized for an afternoon, and check about:processes for flat memory.

A smaller Linux polish lands alongside: menus and panels no longer fade in when you have animations disabled in the operating system. If you turned animations off for a reason, your browser now respects it.

What else ships, and what to retrain

Two usability changes are worth a minute of relearning. First, searching your open tabs gets a real shortcut: Ctrl+Shift+A on Linux and Windows. It focuses the address bar and filters across your open tabs, including synced ones. The trade: the old Add-ons and Themes shortcut moves to Ctrl+Shift+F, remappable in about:keyboard.

Second, the Passwords tool now appears in the sidebar by default. You no longer have to add it manually to reach saved logins from the same window as the page you are logging into.

The Smart Window page-watching feature, where you type /watch to monitor a page for price drops or restocks, is part of this release but rolls out progressively, so do not go hunting for it if it has not appeared yet. Two reliability fixes round out the release: sites like Slack no longer fail outright when an HTTP/3 request is rejected, falling back to HTTP/2 instead, and bookmark imports from signed-in Google Chrome profiles work again. Developers get scroll-driven animations enabled by default, plus scoped custom element registries.

The update drill

  1. Check what you actually have. In Firefox, open Help, then About Firefox, or run firefox --version in a terminal. Distribution packages follow their own cadence, so the version on your machine is the only one that counts.
  2. Re-test the tab gestures on Wayland: click, drag up to detach, drag back. This is the fix you will feel first.
  3. If you run AMD graphics, open a map-heavy page and leave a web app minimized, then glance at about:processes later. Flat memory is the pass mark.
  4. Relearn Ctrl+Shift+A for tab search, and remember Ctrl+Shift+F now opens Add-ons and Themes.

Firefox is on a two-week cadence now, and Firefox 160 is already in public beta. Individual releases will often look quiet. The ones worth updating for are not always the ones with a new look; sometimes they are the ones that stop your tab strip from fighting you.

For context, Mozilla's last big visual shake-up came with Firefox 157, and if you are weighing browsers rather than versions, our best browsers for Linux in 2026 covers the trade-offs. Mozilla's sibling project moved in step too: Thunderbird 157 gave administrators an off switch for chat and FileLink in the same cycle.

Sources

  • Mozilla, Firefox 159 release notes for developers: https://developer.mozilla.org/en-US/docs/Mozilla/Firefox/Releases/159
  • Mozilla, Firefox Release Notes for Enterprise (Firefox 159, October 27, 2026): https://firefox-admin-docs.mozilla.org/release-notes/
  • OMG! Ubuntu, Firefox 159 released: https://www.omgubuntu.co.uk/2026/10/firefox-159-released
  • Linuxiac, Mozilla Firefox 159 improves Linux Wayland support: https://linuxiac.com/mozilla-firefox-159-improves-linux-wayland-support-adds-new-tab-search/