Fullscreen doesn't work properly on Windows

[Gama11]

Goes back to normal after leaving fullscreen mode. Only tested with one of my windows machines so far.

[Gama11]

I can't reproduce the original black screen problem anymore, but fullscreen still doesn't really seem to work on Windows:

It only seems to maximize the window (the window title is still visible), and it doesn't even maximize it properly (there's gaps around the edges).