One of my fences has vanished from my desktop.  The fence still shows up in the Start Menu with all the items within the fence, so it doesn't look like it was deleted; it's just not showing on the desktop.

It's not in any of the recent snapshots, so it must have disappeared more than a few days ago.  I can recreate the fence easily enough, but I'd like to be able to either restore the lost fence or fully delete it so it isn't in the start menu any more.  I don't see anything in the menus to let me do either.  Any suggestions?