Multiple reports suggest that the Firefox tabs in the ‘tab bar’ are completely missing or not showing to some users after the v108 update.
Additionally, the problem makes the little arrows that are frequently used to transition between groups of open tabs when there are numerous of them useless. The arrows continue to show but are now ineffective.
The Firefox update usually comes with some issues. These include faulty mobile ‘suggested URL autocomplete’ crashing problems following the v103 update, and others.
Reports of Firefox missing tabs in the tab bar
Everything appears to be caused by a conflict between the update and userChrome.css. For those of you who are unaware, userChrome.css enables you to essentially alter the appearance and feel of your browser using CSS.
According to reports, the upgrade also introduced a different, albeit less critical, problem. The “Plus” symbol in the “New Tab” icon is no longer perfectly centered, and the icon’s alignment is now slightly off (moved up).
Potential workarounds to recover tabs
While there is no official acknowledgment at the moment, there are a few workarounds to get your tabs back.
“If you just want to return to defaults, you can open about:config and set toolkit.legacyUserProfileCustomizations.stylesheets to false,” a Redditor suggested.
Moreover, you can delete the code line below from your userChrome.css,
For now, there is no solution yet to help fix the inconsistency in the design of the ‘New Tab’ icon.