Comment 22 for bug 762481

This affects me in both Ubuntu 11.10 and 12.04, using both the GTK2 and GTK3 versions (though incidentally, the GTK2 version seems much less crash-prone for me). The application that is affected seems to be totally random, and it isn't consistently reproducible. Every once in a while I notice it happening, then just "killall plank && plank" to fix it.

There seem to be two pieces to this bug, depending on whether the application is marked as "keep in dock" or not:

1) If the application is marked "keep in dock", there are no indicator lights, though the icon *is* highlighted correctly when the application is focused. The applications menu is correct too, with "maximize" and "close" entries, etc. Clicking the icon focuses the currently open window, as expected (or minimizes it if it's already focused).

2) If the application is not marked "keep in dock", it just doesn't show up at all.

In both of these cases, restarting plank temporarily solves the problem.