Thanks for your bug. That looks like a GTK issue, could you get a
backtrace with libgtk2.0-0-dbg libglib2.0-0-dbg installed?
** Changed in: gnome-panel (Ubuntu)
Importance: Undecided => Medium
Assignee: (unassigned) => Ubuntu Desktop Bugs
Status: Unconfirmed => Needs Info
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gnome-panel cannot run
https://launchpad.net/bugs/66189