You would run your Docker install on a custom port. You then have a CMS listening on say 127.0.0.1:8080. You then setup your reverse proxy infront just as before on the host machine. No modification of the container is required.
There’s an example in the manual, or indeed in the guide I wrote here:
If you want to use a different method for configuring your reverse proxy then that’s fine, as long as traffic goes through with the original host header, and ideally X-Forwarded-For and X-Forwarded-Proto headers, then it should all work. Xibo will then see the correct IP addresses.