Full screen reverting back to Window

[Kron]

So I'm having an issue like tittle says.

I do Ctrl + O then select Full screen mode and it changes no problem. The issue I have is if I click near the edges and I mean like 1/2 inch it drops me back into window mode.

So if I want to play full screen mode I need to drag my spell bar and anything else I want to click to the center so I don't trigger this issue.

Also the game looks crisp in window mode, but over saturated in full screen mode and not sure how to fix that.