This plugin allows you to see who’s online. Phase and Discord have a feature where you can view who’s online, and I don’t know why you can’t either.
Think carefully before installing this plugin. Discourse is designed for asynchronous discussion, and a list of online users can be harmful for some communities
Yes, if there is a possibility to hide that status. Imagine if someone spams you when you are online. So you could hide that and no one would spam you when being online