Strange visual glitch after Alt + Tab

[hybrid]

Here's a strange glitch I've seen a few times. It only happens when I ALT + TAB (or Windows key) to desktop and then back to ToME. The only way to fix it that I've seen is to repeatedly open your character window with Shift + C. After 10 or so times the game looks normal again. Not a big deal just a strange bug. Here's some screenshots. One thing you can't see in the pics is that parts of the windows are flashing, for example my Water of Life skill button was flashing weird colors.

http://imgur.com/a/RmqBX