After a system upgrade (Ubuntu 22 to 23), dbus service org.freedesktop.systemd1 is broken.
$ busctl | grep systemd1
org.freedesktop.systemd1 - - - (activatable) - - -
$ busctl tree org.freedesktop.systemd1
Failed to introspect object / of service org.freedesktop.systemd1: Failed to activate service 'org.freedesktop.systemd1': timed out (service_start_timeout=25000ms)
No objects discovered.
Snapd is broken in the ripple effect.
How to start dbus service org.freedesktop.systemd1? How to reactivate it at startup?