I noticed at the login screen my display does not ever go to sleep. It only does after login. Is there some way to configure that and I’m also wondering why there isn’t a default sleep time. I assume it is supposed to be somewhere in /usr/lib/ssdm/.
You can’t touch anything under /usr
You have to check your power management settings in KDEs system settings application. There are some settings for turning off display.
I have set mine to sleep after 5mins being locked and it seems to work fine.
There are only settings under ‘Power Management’ and they don’t seem to apply before logging in. My question has to do with the login screen.
I recall experiencing this too when I used Aurora and KDE on Bazzite. (On GNOME it just goes into suspend mode if you don’t login). You could try looking for relevant settings in the documentation for SDDM. The configuration file is presumably in /etc/sddm, which is writable.
I’m interested in seeing how the new Plasma Login Manager will handle this when it becomes the default and replaces SDDM.
Looking into this, this seems to be SDDM “feature” that the login screen doesn’t automatically go to sleep. You can press ESC to turn the screen off but it won’t automatically do it.
Currently Plasma-Login-Manager doesn’t do it either.