Comment 13 for bug 1404172

This appears to have been addressed in bug #1949970 by making use of a feature of the PAM config. In /etc/pam.d/lightdm, I see e.g.

    -auth optional pam_gnome_keyring.so
    -auth optional pam_kwallet.so
    -auth optional pam_kwallet5.so

From the pam.conf(5) man page:

       If the *type* value from the list above
       is prepended with a - character the PAM
       library will not log to the system log if
       it is not possible to load the module
       because it is missing in the system. This
       can be useful especially for modules
       which are not always installed on the
       system and are not required for correct
       authentication and authorization of the
       login session.

I'll mark this issue as a duplicate of the newer one, even though it should be the other way around.