ya you’re correct, https://docs.docker.com/engine/reference/commandline/daemon/#daemon-configuration-file has a list of variables available to the .json config file. Anything else is ignored.
i was able to modify /etc/init.d/docker (by opening a console to the linux machine: screen ~/Library/Containers/com.docker.docker/Data/com.docker.driver.amd64-linux/tty) on line 39:
DOCKER_OPTS="${DOCKER_OPTS} -H tcp://0.0.0.0:2375 -H unix:///var/run/docker.sock --insecure-registry some.domain.here"
and it will work after restarting the daemon (/etc/init.d/docker restart)
However whenever Docker 4 Mac restarts (ex: restarting computer), this changed is reverted. I suspect it’s because the image is reloaded. Is there any way to modify the change in a more permanent way? (besides trying to modify the com.docker.driver.amd64-linux container, since any updates from you guys would wipe the change too)