Comment 1 for bug 989389

I've been able to reproduce this using a fresh install of Ubuntu 12.04.

Any window that is aerosnapped to the sides (left or right) of the screen will retain their vertical size even if the window is moved to the left or right of its snapped location.. the size reverts back to the pre-snapped size if the window is moved vertically down. The size reversion on a veritcal move happens when the window is locked in aerosnap or after its been moved horizontally.