https://bugs.winehq.org/show_bug.cgi?id=39421
--- Comment #14 from Jonas Maebe jonas.bugzilla@gmail.com --- One other thing I tried yesterday: call glFlush once a second, in order to have a fixed upper bound for those UI elements to appear. This had a (to me) quite unexpected effect: about every second, the screen contents suddenly changed to those from somewhere within the past second for a very short while, and then continued updating normally. I have no idea what could cause that.