I am constantly experiencing a weird bug when using Coherence mode, see the following screenshot:

Basically, whenever a Windows application has focus, a square window shows only the Windows "desktop", i.e. any windows apps running underneath, giving a kind of "portal"-effect.
The square is always in the same place, and I have noticed this behaviour on 2 different Macbook Airs (2011 and 2013), both in Parallels 8 and 9 (IIRC, version 6 as well).
Any fixes for this?

Basically, whenever a Windows application has focus, a square window shows only the Windows "desktop", i.e. any windows apps running underneath, giving a kind of "portal"-effect.
The square is always in the same place, and I have noticed this behaviour on 2 different Macbook Airs (2011 and 2013), both in Parallels 8 and 9 (IIRC, version 6 as well).
Any fixes for this?