Comment 11 for bug 931473

I seem to be able to reproduce this, but it's difficult on a quick PC. It would probably be more apparent on something lower spec than an i7.

It seems to happen more if you're moving the mouse whilst clicking the menu area. So if you click a menu then move the mouse the next item it happens more often. Also if you move the mouse to a menu, click and then pull the mouse away before the menu has fully displayed then it often breaks up.

See the attached picture. I moved the mouse to the menu and then away and the menu looked unfinished.