menu in TBB 5.5.a4 doesn't work anymore
I recently upgraded TBB to 5.5a4. After restarting the browser I noticed that the menu doesn't work anymore. So if I click on the NoScript icon, the green onion or other items nothing happens. I tried to use the keyboard and press Alt+Char to open a menu item. Also this doesn't lead to any action. Pressing Alt alone shows the menu bar. I have this issue only with TBB on one machine. The upgrade on another machine went fine and TBB works as expected there.
Can i provide you with more helpful information? What do you need?