After upgrading to 12.04, Skype and Mathematica randomly disappear from the unity launcher so that they are unusable anymore. Calling them again from the dashboard does not bring it back, since this just launches other instances of the programs. The only thing I can do is reboot. Even restarting the GUI or login-logout does not solve it. Only reboot will do.
I assume it is related to their QT framework and I am in serious need of a fix.
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