Always only enable docker.socket and not docker.service.
But keep in mind to modify systemd-networkd-wait-online.service
(otherwise you wait 2 minutes for starting docker)
https://unix.stackexchange.com/questions/381448/systemd-networkd-wait-online-failures
sudo systemctl edit systemd-networkd-wait-online.service
# or
sudo SYSTEMD_EDITOR=micro systemctl edit systemd-networkd-wait-online.service
[Service]
ExecStart=
ExecStart=/usr/lib/systemd/systemd-networkd-wait-online --any