In one Firefox window both the "+" sign to add another tab and tab groups symbol have dissappeared. Can't access tab groups nor add tabs anymore.
Both are present in other windows I have open inside of Firefox. Software OS X 10.8.4 (12E55) FF: version 22.0
All new tabs open in a different window than the one with missing tab groups and "+"-sign even when generated from this window. Closing open tabs does not help.
Alla svar (2)
Maybe you should move the tabs to a new window and close this window if it isn't working properly.
It is probably not possible to repair this window.
This could be a problem with an extension that you have installed.
Run Firefox in Safe Mode and see if the problem still occurs.