Gdm offers different login methods randomly

[Thomas]

I have enabled fingerprint login for my device. GDM is offering sometimes hybrid authentication like: password or swipe finger. But sometimes it offers only fingerprint. This is very strange and I like the hybrid variant. So it changes its behaviour between several reboots. I can not relate this this to any special event or anything.

ProblemType: Bug
DistroRelease: Ubuntu 20.04
Package: gdm3 3.36.3-0ubuntu0.20.04.3
ProcVersionSignature: Ubuntu 5.4.0-72.80-generic 5.4.101
Uname: Linux 5.4.0-72-generic x86_64
NonfreeKernelModules: nvidia_modeset nvidia
ApportVersion: 2.20.11-0ubuntu27.16
Architecture: amd64
CasperMD5CheckResult: skip
CurrentDesktop: XFCE
Date: Wed Apr 28 08:49:00 2021
InstallationDate: Installed on 2019-12-19 (495 days ago)
InstallationMedia: Ubuntu 19.10 "Eoan Ermine" - Release amd64 (20191017)
SourcePackage: gdm3
UpgradeStatus: No upgrade log present (probably fresh install)
mtime.conffile..etc.gdm3.custom.conf: 2021-04-23T01:47:10.096850

[Sebastien Bacher (seb128)]

Thank you for your bug report. Could you provide a 'journalctl -b 0' log for each of the cases?

[Thomas (t-hartwig)]

Added two files as wished.

Further observation: sometimes it is switching between both methods when re-selecting the login user from the list.

[Thomas (t-hartwig)]

journalctl --unit=gdm.service

There is following strange line:

Apr 30 19:07:27 seal gdm-fingerprint][8190]: gkr-pam: no password is available for user

[Launchpad Janitor (janitor)]

[Expired for gdm3 (Ubuntu) because there has been no activity for 60 days.]