Replying to Online light next to name

Hope this isnt a repost if it is let it die or get it deleted.

Ok so i was thinking in threads when you look at somebody's name on the left side of it there could be a little green dot or red dot for when they are on or offline.

So that way when your in a thread you can see immediately if that person is currently online.

Little green dot(light) on left side of name means online

Little red dot(light) on left side of name means offline

Thoughts?