Comment 2 for bug 1083532

I have the same issue. Restarting libreoffice (sometimes a few times before it works) is required to make the menu usable again. If there are multiple documents open, it can be that one window has a menu that works, while another has a menu which doesn't. Also, the dialogs themselves are fine - for example, clicking on the save button will bring up the save as dialog for a new file (but File > Save as... will not).