Comment 6 for bug 1002602

I'll throw in what I tried to say in my own bug report (duplicate) here:

This isn't happening just to windows that lose focus.
This can happen to any window that /changes/ focus.

On occasion windows will acquire focus and become blank.

Of particular annoyance are dialog boxes that appear blank.
This stops all interaction with the parent window.

This does sound very similar to bug 729979.
Unfortunately the comments on it are remain inconsistent.