Dear Maintainer,

* What led up to the situation?

Upgrade to systemd v256.7-2 and its following change:

| * Disable utmp support, not y2038 safe. utmp support in tmux has been
|   disabled, so autopkgtest should no longer break

As a result of which no /run/utmp or similar gets created
during system startup.

* What was the outcome of this action?

After the systemd upgrade, lightdm started reporting

  lightdm[1748]: Failed to write utmpx: No such file or directory

in the journal.

* What outcome did you expect instead?

No messages, as suggested by the following wiki:

https://wiki.debian.org/pam_lastlog2%20and%20wtmpdb#For_maintainers