[Trisquel-users] Invisible menus in LibreOffice

[bm-2cwce5abrzcyn1hzwsb33z4btaxgamtogq]

It's the first time I use this laptop with LibreOffice, or any office pack.  
And to my surprise, parts of the menus are invisible. They do work, but it's  
a pain to guess. I noticed Trisquel still uses the 3rd generation. So I got  
to the PPA and upgraded to the latest in the 4th generation. So far so good.  
Menus are still partly hidden. I attach a picture to get an idea.

Any idea how one can fix this?
<<attachment: Screenshot from 2014-04-10 19:14:09.png>>