Having a system tray on a panel will crash plasmashell at login with a black background and no panel, adding it to an empty panel or adding a "default panel" will crash plasmashell as well. No backtrace since the desktop sort of keeps running (krunner works as well as my shortcuts). Reproducible: Always Steps to Reproduce: 1.Update 2.Login to any session X or wayland 3.Behold your desktop with no panel and black background.
krunner running doesn't mean plasmashell is You should still get a backtrace. We need something to go on, as this report tells me nothing, and it clearly isn't affecting everyone - otherwise we'd be seeing a lot more. What makes you say it's because of the system tray being on a panel?
....I know..... I just downloaded a new iso of Neon unstable from here: http://files.kde.org/neon/images/neon-devedition-gitunstable/current/ Created a new virtualbox vm and boot it up.The same problem is there "LIVE". I got the desktop with a black background, unable to right click on it no panel Here is what i did..... I check that the process for "plasmashell" was there, it was but it was marked as "stopped" under the cpu tab on ksysguard and got automatically killed just a few seconds later. Opened up krunner (alt+space) and ran "plasmashell", i got the default desktop background, can right click on desktop but no panel still. Added a "default panel", got me back to the "black background state", plasmashell process is mark as "stopped" and gets kill a few seconds later. Ran "plasmashell", added a empty panel, all good, and then added "system tray" widget, "black background state" again. Ran "plasmashell", the empty panel shows up but without "system tray", added it again......... "black background state". I literally added all widgets but "system tray" to 2 empty panels, no issues. So the common denominator in all cases is the system tray widget being present, that's my reason. As for the backtrace, i thought DrKonqi did not run when any of this happens, it did i saw the process on ksysguard but its window does not shows up. Clicking "Show application window" does nothing. Dunno if DrKonqi saves something somewhere that may help, but its process dies as soon as the plasmashell one does. Even though i have very little knowledge about gdb i know how to attatch it to a process and run "bt". In this case i did that opened up a terminal and ran "gdb "plasmashell", but when run "bt" all i get is "no stack" before or during the issue. Also when i run gdb (no process) and then "attach plasmashell" i get "Illegal process-id: plasmashell" no idea why. Hope this helps a bit, i know you can do much without a backtrace and even less if you can't reproduce the issue.
This sort itself out today after i updated my main system and vm. Whatever it was is not happening anymore. Maybe a package/configuration conflict. Also downloaded today's neon unstable iso to check out as i did with yesterday's one, all good.