On ubuntu 12.04 64 bit, any change in size of Scratch's window causes it to turn black and slowly shrink down to a thin strip. Quite an interesting bug!

Here's a video:

Fullscreen (via the window button - not Scratch's presentation mode) makes the window fullscreen, but there is no repaint - the window remains black until it is changed back into window mode (by clicking the rectangle). This issue also happens on my 32 bit test OS. 

Here's the command I used to launch, in case it's helpful:

Any idea what might have changed in the VM that could cause these issues? Could this be related to changes made for compiz compatibility?

-Amos