@mbelew mmos sets up a fairly complicated environment.
it runs docker on top of raspi-os
and the starts a docker container (Linux os)
which then runs MagicMirror
the mm config and modules are stored outside the container on the raspi-os file system in differently named ( as compared to normal ) folders.
so none of the instructions to maintain them are the same
you will have to learn and follow the mmos commands for all that.