SUMMARY Since I connected a new screen to my PC (and this may be unrelated) it sometimes happens that when I wake my PC from standby (with that other screen turned off before and after standby) plasma seems to have crashed: - The wallpaper is the default one - Sometimes the lockscreen is the default one but sometimes it keeps my lockscreen (when I enter my password at the lockscreen I had to click on the password field or it didn't enter it) - The panel at the bottom disappeared and when I click the Meta/Windows key nothing happens - When I move windows like the konsole window, the window becomes invisible until it's at the new place In system monitor it shows that plasmashell is running (started by systemd) and that startplasma-waylandsession is running (started by systemd->sddm->sddm-helper->startplasma-wayland->kwin_wayland) I'm using Wayland on Debian11/KDE. When I enter journalctrl -b it only shows very three entries for the day at the bottom like "systemd: Started konsole." and many for the previous day even though I had my computer running for quite a while today. (Note there's also a loss of bash history when using Wayland on Debian and I used to restore it from backups until this became too frequent. Wayland-KDE bugs really should get fixed.) Please let me know if there's anything else I could run to investigate this. I usually try running killall plasmashell and kstart5 plasmashell to get it working again and if that doesn't work I have to end the session and log in again. STEPS TO REPRODUCE 1. Use Wayland on Debian11/KDE 2. Put the PC on standby 3. Wake it OBSERVED RESULT Sometimes plasmashell seems to have crashed EXPECTED RESULT Plasmashell should not seem to crash, there should be no problems after waking the PC. SOFTWARE/OS VERSIONS Linux/KDE Plasma: Debian 11 KDE Plasma Version: 5.20.5 KDE Frameworks Version: 5.78.0 Qt Version: 5.15.2 ADDITIONAL INFORMATION
killall plasmashell and kstart5 plasmashell doesn't work to get it working again: it looks just like before. Please don't just say Debian has an old version of KDE. *IF* that is the cause of this then please do something about it.
Now something similar happened: after resuming from the lockscreen the resolution of my properly detected screen (I checked with systemsettings5) is turned down to the resolution used on the other screen and lockscreen is still visible but in a surrounded by black and mostly covered with konsole messages about deprecated Qt syntax. When I maximize the browser the display issues disappear. I'm not using a proprietary graphics driver or alike. Maybe the screenshot worked so I can attach it
> Linux/KDE Plasma: Debian 11 > KDE Plasma Version: 5.20.5 I'm afraid Plasma 5.20.5 is no longer maintained because it's almost impossible to debug issues like this on old versions of Plasma. The fact that Debian chooses to ship unmaintained versions of Plasma to users which are undebuggable by Plasma developers is a decision that frequently causes frustration for both Debian users and KDE developers and Debian's packagers. If you would like to stick with Debian, I would recommend that you upgrade to 5.24 or 5.25 by using Debian unstable, or wait until Debian Stable ships a newer version. Furthermore, if something crashed, we need a backtrace of it so we can figure out what's going on. See https://community.kde.org/Guidelines_and_HOWTOs/Debugging/How_to_create_useful_crash_reports.
I don't know if something crashed, maybe there is something specific that I could check if it's running. It could also be two concurrent bugs. I suspect it has something to do with the display settings done after connecting the other display which still shows under Displays even when not turned on. In specific, that I checked "For only this specific display arrangement" rather than "For any display arrangement" may be the cause / may be the needed setting to replicate this bug (the two displays have different resolutions). When waking from standby the login screen only showed my user and "Switch user" when I click on "Switch user" the resolution of the lockscreen is back to how it should be and when I login it's still the screwed up resolution (too small and graphical flickering glitch bugs). The only thing that works is loging out via (killing some specific process or) running qdbus org.kde.Shutdown /Shutdown logout.
What could be done when the bottom panel doesn't show and the wallpaper is set to the default one when restarting plasmashell doesn't help with that without having to log out (and close all apps)?
Further input and potential help may be found here: https://unix.stackexchange.com/questions/714159/what-causes-plasmashell-to-crash-after-waking-from-standby-wallpaper-set-to-def
It is related to the (connection to the) display and sometimes (maybe even always by now as I'd need to test this) turning on the display ends the session. Maybe I'll revisit this once Debian has upgraded to Debian 12 with a newer version of KDE.