I’m running Niri + Noctalia on CachyOS on a Dell XPS 13. The laptop’s fingerprint sensor is supported by fprintd and I was able to follow the instructions on the Arch Wiki page for fprintd to get it to prompt for a fingerprint scan for most of the software I want to work when I am already in the OS, but I can’t figure out what I need to update in /etc/pam.d/ to get the login screen to accept a fingerprint instead of a password.
OK, this is confusing. I clearly need to track down a good stack explanation, because I don’t understand what’s going on here at all.
It looks like I’m running sddm. I have it running in ps aux and there are config files for it. This gives me a good jumping off point, I’ll poke around a bit and report back with what I find.