This bug still happens in 12.04 beta with all updates applied as of today. I cannot find a reliable way to reproduce it, but it seems it only happens when switching to another application from chromium with Alt-Tab.
** Changed in: unity-2d (Ubuntu) Status: Fix Released => New -- You received this bug notification because you are a member of Desktop Packages, which is subscribed to unity-2d in Ubuntu. Matching subscriptions: dp-unity2d https://bugs.launchpad.net/bugs/735205 Title: [window management] Alt tab does not switch to the desired application but instead set the urgency flag on the window Status in Unity 2D: Fix Released Status in “unity-2d” package in Ubuntu: New Bug description: When a window is selected with alt-tab, it is not opened, but its icon wiggles. Selecting the window with the mouse works. Using unity-2d maverick ppa. To manage notifications about this bug go to: https://bugs.launchpad.net/unity-2d/+bug/735205/+subscriptions -- Mailing list: https://launchpad.net/~desktop-packages Post to : desktop-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~desktop-packages More help : https://help.launchpad.net/ListHelp