`--log-driver=none` is used for all Docker containers now.
All these containers are started through systemd anyway and get logged in journald,
so there's no need for Docker to be logging the same thing using the default `json-file` driver.
Doing that was growing `/var/lib/docker/containers/..` infinitely until service/container restart.
As a result of this, things like `docker logs matrix-synapse` won't work anymore.
`journalctl -u matrix-synapse` is how one can see the logs.
Slavi Pantaleev
Hugues Morisset