Comment 3 for bug 659851

Interestingly: I am still getting this issue when I switch to the external monitor (disabling my laptop's built-in screen). But I've found that if I use TwinView to show either the same image or a split screen image on both screens, it doesn't come up.

So as a workaround, I can just leave my laptop's screen turned on when I'm using the external monitor. (Waste of power though.)