I am about to move my sites to VPS (Ubuntu 16, Apache, with Webmin VHM).
In Webmin.com I came across this article that says:
WARNING : Running Webmin under Apache is almost never necessary unless you are on a very low-memory system that is already running Apache. Doing so will make Webmin slower, break some features and force use of the old ugly UI.
Is it only a bad phrasing? Because I can't think of any reason why Webmin will warm people not to use Webmin and Apache together --- Almost any Webmin user I know, uses Apache (or Nginx) as its server software.