Just recently moved into darcs version of xmonad. Config works exactly the same.
Noticed that with the darcs version chromium fullscreen video does not bleed.
As a test i went back to using haskell xmonad 0.11.1 and the video did bleed.
So the culprit was not chromium but xmonad version 0.11.1.
Is the darcs version ever going to be implemented to the stable release (haskell). I noticed there is a thread for "New Release" but nothing concrete as to date. Granted new releases take time but just wondering.
When chrome is running on fullscreen (F11) and i change to different pages the window client expands (bleeds into the neighbor screen). It's like if it were zooming in. I tried it with firefox and that does not happen. I provided some screenshots.
Just in case someone ask, here is a snippet of xmonad.hs file: