Windows occasionally loose focus when quickly Alt+Tabbing

[Mjumbe Wawatu Ukweli]

When I quickly Alt+Tab between two applications (i.e., Alt+Tab-release, Alt+Tab-release, ...), sometimes neither application is focused when I stop. I have to click on the window (or Alt+Tab again) in order to regain focus. I do not know what has focus in these instances, as when I type nothing seems to happen.

To reproduce:
1) Open two (or more) applications
2) Quickly (about twice/second will do) Alt+Tab between two applications (i.e., Alt+Tab-release, Alt+Tab-release, ...) until Unity's top bar shows a blank application title

~$ lsb_release -rd
Description: Ubuntu quantal (development branch)
Release: 12.10

~$ apt-cache policy unity
unity:
  Installed: 6.6.0-0ubuntu1
  Candidate: 6.6.0-0ubuntu1
  Version table:
 *** 6.6.0-0ubuntu1 0
        500 http://us.archive.ubuntu.com/ubuntu/ quantal/main amd64 Packages
        100 /var/lib/dpkg/status

[Sami Jaktholm (sjakthol)]

Thank you for taking the time to report this bug and helping to make Ubuntu better. This particular bug has already been reported and is a duplicate of bug 1035628, so it is being marked as such. Please look at the other bug report to see if there is any missing information that you can provide, or to see if there is a workaround for the bug. Additionally, any further discussion regarding the bug should occur in the other report. Feel free to continue to report any other bugs you may find.