Created attachment 170576 [details]
gdb backtrace, I hope this is useful - it's my first one, and drkonqi didn't work

SUMMARY

After creating a panel and trying to drag & drop between the first and second panel in "Show Panel Configuration" mode, my Plasma ended up in a very messed up state, including a crash.

STEPS TO REPRODUCE

I have not attempted to fully reproduce the issue yet. Here's what I was doing to the best of my recollection, but I doubt it would reproduce cleanly.

1.  Create a second panel
2. Attempt to drag the notification area to the second panel, fail as it gets stuck on the desktop
3. Drag it back from the desktop to the panel
4. Attempt again. Things start to get weird here, I think the widget vanished from view completely
5. Attempt to add a notification widget to the second panel.

OBSERVED RESULT
 
Plasma is in a generally messed up state, including

1. Plasma crash, see attached backtrace
2. No tray widget is displayed anywhere, even though the "Add widget" interface claims there should be two. (See attached screen shot)
3. Minor visual glitches like the "Add widget" button on the second panel being off-center and as a consequence being cut off on a de-floated floating panel  (see attached screen shot)

I've also attached the appletsrc file that resulted in case that helps.


SOFTWARE/OS VERSIONS

Neon Dev

Linux/KDE Plasma: 6.5.0-35generic
KDE Plasma Version: 6.1.80
KDE Frameworks Version: 6.4.0
Qt Version: 6.7.0

ADDITIONAL INFORMATION