I started up Debian's lyx 1.6.7 today. The menus didn't work. Neither
did they work for my self-compiled lyxes. Very strange. The main menu
was there, but it was impossible to pull anything down!
So I logged in as another user, and LyX worked fine there. So, a user
setup problem.
Removing .lyx/ did not help. So I used "strace" to find the difference
between the two users.
I found there is also a per-user .config/LyX/ directory. I removed this,
and now LyX worked fine!
I don't think I ever modified anything in that directory - I surely
haven't turned the menu system off deliberately.
Any idea what might have happened?
Helge Hafting