White bar over menu bar? I'm experiencing this weird bug on OS X El capitan.

There is a white bar over most of my menu items in the top right of my screen. The items are still there and are interactable.

Anyone got any ideas? A quick google search didn't seem to give me any ideas for it.
For me this happened on one of the monitors that I was extending my macbook pro's desktop to, not all of them though.

Easiest fix, expand a program to full screen and then minimize it again, somehow the animation of expanding fixes it.