Comment 18 for bug 1539011

I was about to report a new bug about resizing but I found this one.
I've noticed the problem is only with right and bottom border of an app window. the top and left are fine whenever side I start resizing from. Also it looks like the title bar does not stutter when resizing, just the rest of the window. I've recorded a short video about it: https://youtu.be/3H48UBpXUUo