Question about facebook?

[Babyface]

I don't know if there is a glitch on facebook or something, but I notice when my friend is online their is no green bar on their chat box, just their picture and name. What I noticed is that the person sees my messages, but then the person looks as if they're not online.

Is this a glitch, or some cool trick for a person to not look visible online but see your messages?

[Andee]

Well at the bottom right there is a 'settings' box if you are on the desktop site. You can 'go offline' yet still chat with people. Haha. It's just something they've included. The people who go offline though can't see who's online so technically you would have to message them first

[cs1234]

Sometimes they can make themselves appear offline. At times it might just be because they are signed in to fb on their phone.

[Maria]

Sometimes, they can make themselves go offline from specific people. Say, he doesn't wanna chat with X. But he still wants to chat with Y and Z. So, in the chat box, he can click on go offline to X. But he's still online to Y and Z!