Kubuntu 15.04, plasma-workspace 5.2.2-0ubuntu3

While poking around at my panel widgets, and resizing the panel, I did something that made it stop responding to clicks.  IDK what exactly.  I did end up adding a 2nd instance of the system tray widget to the panel, and then doing a bunch of stuff trying to move or get rid of it.

 (I eventually found the howto animation, after I locked up my panel.  I was trying this because my systray wasn't showing icons for apps that put an icon in the system tray (like Deluge).  It used to work on fluxbox.)

This may be the same as https://bugs.kde.org/show_bug.cgi?id=344542, but it's not happening by itself.  I didn't have a problem with this until I started messing with the panel settings, though, and that bug sounds like it happens at any time.

Clicks on the panel, and right-click on the desktop, did nothing.  Normally right click on the desktop would bring up an actions menu.  Panel widgets respond to mouseover, but not to clicks.  The pointer isn't grabbed by another app.  I can alt-tab ok, and even find all my windows thanks to the Grid switcher Desktop Effect, so I can do without being able to click on the taskbar part of the panel, too.   The panel is updating when windows minimize / unminimize, but it's not accepting clicks.  (not even in the launcher.)  Fortunately I don't care about that, since I start everything from screen(1) in a konsole anyway. :P

I don't intend to relog soon.  If anyone wants me to check anything with gdb, I'm willing.  I know C++, but haven't ever looked at KDE / Qt.  I could even give shell access to a gdb session if someone wants to poke around at the wedged plasmashell process.  (send me an ssh public key and I'll get something set up.)


Reproducible: Didn't try

Steps to Reproduce:
1. fiddle around with panel width sliders, and/or widgets.