@OrangeMirror the current docker setup will only work for multiple instances
IF
you use the MM_CONFIG_FILE environment variable to run instances off different config files,
or
the MM_PORT env variable to override the port if using the same config.js
all the files will come from the ONE folder tree ~/magicmirror
so this means you would have to setup multiple entries in the compose.yaml to launch multiple instances (with the different config parms)
You have to change the container name too
this is because all the DATA used by the container is external (on docker host filesystem) and not IN the container
an example NOT using docker, but same idea here
https://docs.magicmirror.builders/configuration/introduction.html#advanced-configuration-and-frequently-asked-how-to-configure-examples