I don't know how to describe the problem so here's the screenshot:
It's not a big deal because once I move my cursor around the black area, it's gone... But it's quite irritating since well, it's irritating.
And it only occurs whenever I minimize my Chrome
Since I'm not sure whether it's Chrome problem, Windows problem or my graphic drivers? Imma post it here >_<
Also, my graphic driver is NVIDIA GeForce 332.21