SUMMARY Today to activate the fingerprint authentication we must : - install packages like fprintd ... etc. - modify in /etc/pam.d/ the file sddm by adding pam statements and create a file named "kde" with some pam statements. This work is for a techie person. If kde detect a fingerprint reader, it must do the job. SOFTWARE/OS VERSIONS Windows: macOS: Linux/KDE Plasma: (available in About System) KDE Plasma Version: 5.25.4 KDE Frameworks Version: 5.97.0 Qt Version: 5.15.5 KDE Gears 22.08.0 ADDITIONAL INFORMATION
Unfortunately KDE code doesn't have input into how this should be done, because the exact setup procedure and the packages needed vary by distro. So this is something for the distro to do, not us.
I sent a bug report to openSUSE. https://bugzilla.suse.com/show_bug.cgi?id=1202740 the answer "... Agreeing with Frederic that this should be handled by GNOME/KDE, not YaST." Perhaps opensuse and kde must join their effort.