Improvements to tree tabs and the vertical sidebar
This update aims to make the built-in tree tabs more reliable by improving session restoration, tab dragging and sidebar behaviour.
More reliable tab trees
- Fixed an issue where newly opened tabs would sometimes remain invisible until another tab was selected, including links opened from pinned tabs.
- The restoration of saved tab trees has been improved, including tabs that load in the background and trees inside tab groups.
- Fixed an issue where dragging a branch would sometimes show where it would move without actually moving it, along with incorrect placement and ordering. Moving branches containing split-view tabs now preserves both panes and their child tabs more effectively.
- The indentation and alignment have been corrected so that parent tabs, children and siblings are easier to distinguish. The visibility and labels of the expand/collapse controls have been improved.
- The opening of bookmarked trees in new windows has been fixed, including in private windows. This ensures that bookmarks retain their order and nesting.
- Unnecessary work when restoring and displaying tab trees has been reduced.
More control over tree behaviour
- The option to automatically collapse other trees when switching between them is now off by default. If you previously chose a setting explicitly, your choice is preserved.
- You can access more tree controls directly in Settings, including options for indentation and nesting limits, the tab that becomes active after a tab is closed, and how dropped links open.
- When an unloaded background tree is expanded or collapsed, its parent tab is no longer unnecessarily loaded.
- Switching to horizontal tabs no longer creates new tree-only parent/group pages. Any existing tree relationships remain available when you switch back.
Sidebar fixes
- Fixed an issue where pinned tabs would disappear or become unclickable when displayed with their titles.
- The unexpected collapse of the hover-expanded sidebar while a right-click menu was open has been fixed. Cancellation of hover expansion when the pointer leaves the window has also been improved.
- Fixed an issue where full-screen video would leave the sidebar visible and shift the video to one side.
- The issue of the collapsed sidebar becoming too narrow for tab icons when the sidebar controls were hidden has been fixed.
- The clipped text and misaligned icons on the 'New Private Tab' button in the collapsed sidebar have been fixed.
Tab appearance
- By default, unloaded tabs keep their colourful icons. You can turn greyscale icons back on in the 'Appearance' settings. The tabs still look faded when unloaded.
- Tab titles are no longer italicised by default. If you would prefer this indicator for unread background tabs, enable “Italicize unread tabs” under 'Tab display'.
Security
Waterfox 6.7.2 incorporates the security updates outlined in Mozilla Foundation Security Advisory 2026-85.