If you look at the test case you can see it affects every Dock type window that is hidden rather than destroyed. The clock was fixed by making destroyed windows get their shadow cleaned up properly, this one apparently needs hidden windows to get their shadow cleaned up properly. It is a rather general problem though.
If you look at the test case you can see it affects every Dock type window that is hidden rather than destroyed. The clock was fixed by making destroyed windows get their shadow cleaned up properly, this one apparently needs hidden windows to get their shadow cleaned up properly. It is a rather general problem though.