I’d like to run some system commands after creating my virtual servers
There isn’t any “post-install” entry in virtualmin side menu,
and nothing relevant under “System Settings”.
(specifically, i want to set File-ACL permissions to the newly created directories, but that’s irrelevant)
Take a peek in System Settings -> Virtualmin Config -> Actions upon user and server creation, you can use the options in there for running commands after a Virtual Server is created.
So for the sake of others like me who read this and also overlooked the drop-down box: