I have Fedora 33, the KDE spin, and am using Plasma.
I found that when I log out and in again (but not when I log in after booting up) I get a black screen and the prompt that kded5 needs the kwallet password. I type my user password but am still stuck in the black screen until I reboot by Ctrl+Alt+F2 and then Ctrl+Alt+Del.
To work around this I disabled KDE Wallet in settings, but then the Network Manager applet silently failed to save the Wi Fi password and the Wi Fi password prompt appears at login. SOmetimes it appears, again, on a black screen,. and leaves me with a black screen after I type the password!
I worked around this, too, by going into the network settings and saving the password for all users. But this setup has too many workarounds. Is there any way to troubleshoot the black screen situation, and also to make sure the wallet auto-unlocks on login?