Hm, looking at the GDM code it checks specifically if the logind provider is systemd[1], i'll probably have to send a patch to GDM to also account for gardenerdb [1]: https://gitlab.gnome.org/GNOME/gdm/-/merge_requests/289/diffs#0cc1139e3347f573ae1feee5b73dbc8a8a21fcfa_128_126