LibreOffice problem integrating with Unity
Solution 1:
I had the same issue. After I installed the lo-menubar (see synaptic) i haven't seen this issue (to be sure I will need to test longer). I'm wondering if you have the same experience.
Solution 2:
In Ubuntu 12.04 lo-menubar actually causes problems and removing it after upgrading from 11.10 has lead to the unity integration working much better.