Well,you go to forum and if any player is online click on he name and it will show whered he are in game (if he is online) like I am on public8,this will be showed in forum like
Whered I am:/jo public8
Last room I was:/jo public8
It will apear in you Profile (public profile)
You can select if you will let peoples the room that you are in or not.

This used to be a thing, but it got removed because it was buggy af.

what you can do, is go ingame and type /sa username to find what room a person is in.

^/sa is just a much easier way of doing things, let's not make something that can be simple complicated