Also asked @ launchpad: https://answers.launchpad.net/ubuntu/+source/xserver-xorg-video-ati/+question/196690
On Kubuntu 11.10 and below, when I went full-screen (flash, game, whatever), the app full screen took up just one monitor. But after upgrading to 12.04, it spans both screens, which is ugly on some computers and causes loss of viability on my others where the vertical resolution differs.
How do I fix this? I want full screen to take one monitor; not span across two.
This happens regardless of graphics cards; fails on both integrated intel cards and nvidia ones. I have three computers; all have this problem.