What exactly does "online" mean in the Fortnite friend list?

I was wondering what "Online" actually means.

It seems to me as though people waiting in lobby are "BATTLE ROYALE LOBBY n/4", and people in a game are "PLAYING BR .." but what is "Online"? Launcher open on the desktop but game closed? Creative? STW? Or is it just the same as br lobby?

Online usually refers to console players.

It's when they exited out of Fortnite but didn't actually stop the application, i.e it's when they just press home while they were playing and are now playing a different game.

Otherwise it means that they are still entering the game.

If it isn't for the first reason i mentioned then it's because they are still entering the game (their Fortnite is launching), or that their launcher is open (a premature part of opening the game).