I am on Fedora 42 KDE Edition, and I’ve been getting this problem almost regularly since past couple of days. Below is the exact error message.
Blockquote
The screen locker is broken and unlocking is not possible anymore. In order to unlock it, switch to a virtual terminal (e.g. Ctrl+Alt+F2), log in to your account and execute the command:
loginctl unlock-session 2
Then log out of the virtual session by pressing Ctrl+D, and switch back to the running session (Ctrl+Alt+F1).
Should you have forgotten the instructions, you can get back to this screen by pressing CTRL+ALT+F2
My laptop is supposed to “Do nothing” and only screen is supposed to turn off when kept idle, but if I leave it idle for too long (approx 30 minutes to an hour). I do not get my SDDM and have to force shutdown my PC. I suspect the latest plasma update to 6.4.1 might have caused it as this error never occurred when I was using plasma 6.3.