Any help or insight would be appreciated. After the latest update and restart, I logged into my machine to find it all blank. No wallpaper, no trays, right click does nothing. However, the terminal still runs as do programs launched through the terminal.
The two apps, set to autostart at boot time - firefox and telegram launch without issue. Any insights?
Welcome to the forum! 
What you are describing sounds like Plasma pooped itself, which unfortunately does happen from time to time, and this is exactly why having backups is crucial.
The best/only way to fix this is to log into a tty, nuke all of your Plasma-/KDE-specific configuration files under ~/.config and ~/.local/share, empty ~/.cache, and then start setting things up to your liking again from the defaults — which are stored in /etc/skel/.config and /etc/skel/.local/share, but they should be recreated automatically upon the next login.
For whatever it’s worth, I’ve just been through the same thing again myself yesterday, but luckily I had backups.
I was afraid this would be the case. Let me try it out and report back.
This does not seem to have done the trick. I’m now down without autolaunch for firefox and telegram, but still able to open terminal and launch firefox.
Log into a tty with Ctrl+Alt+F3, and then run the following commands… 
sudo systemctl stop sddm
rm -rf ~/.cache/*
mv ~/.config ~/.config.bak
mv ~/.local/share ~/.local/share.bak
cp -R /etc/skel/.config ./
cp -R /etc/skel/.local/share ~/.local/
sync
sudo systemctl start sddm && exit
You should be able to log in now, and then later you can start moving stuff back from the .bak directories if you want to. You will also have to add firefox and telegram-desktop to the Autostart section in System Settings.
So you were somehow missing parts of the Plasma desktop?
The packages were uninstalled?
I suppose that makes sense for it not working.
This topic was automatically closed 2 days after the last reply. New replies are no longer allowed.