I am running Ubuntu 16.04 LTS and it was working fine. There was not any issue with the display. But today morning when I turned on the laptop from sleep, it has started to display a white grainy background around the dialog boxes and the corner buttons (close, minimise, and maximise buttons) are not visible. I can see some sort of change in the grain pattern in the position of the buttons when I place the mouse over the buttons. The buttons are working though.
The display around it is fine, as you can see.
lspci -nnk | grep -A3 VGA
, just don't dump the output into a comment.