LÖVE

I can confirm:
Compiz + Windowed + !Nvidia = undefined behaviour
The !Nvidia part is personal experience, don't know if others have this as well.

OK , i checked it with another openGL application ("pong2") and it's not löve specific.

One thing I've noticed, since pong2 captures the mouse cursor when it isn't paused (thus rendering the user unable to move the window most of the time) the movement bug was not really obvious - had not I looked for it specifically I would probably not have noticed it!

Maybe do the same with löve? Or at least provide an option to do the same?

-Ido.

You can do that with:

love.system.grabInput( true )

With my Ati card things get ever weirder: if you move the window, only the decorator gets moved but not the window content (while dragging). It keeps updating the game, only at the wrong place, until you release the window. It's not pretty, but isn't critical at all.

See, I can blame ATI!! I want my Nvidia back! (I really should go to the store, before my warranty expires)

Ati's OpenGL Drivers are crap. They are sometimes 200% slower than the nvidia ones.

This is mainly an issue with composite on Linux in general. Most Linux gamers know to disable Compiz or Strange Things And/Or Reduced Performance Will Happen.

Supposedly a solution is on the way with DRI2, which will make the composite manager aware of other OpenGL applications. Until then, just leave a note in your readme file telling people to disable desktop effects.

Well, since I have the possibility to praise Nvidia (again), allow me:
I never had such problems with the Nvidia drivers, maybe they already did check, or maybe it just handled it much more effective.