Tell me if this doesn't work... Type in the username of the person you want to check. It will tell you if their online (it might switch between online and offline if you or they have bad internet-). Note it might take a second for it to figure it out, especially if you wait for the syncing screen to go away (about 5 - 15 seconds).
@BKFighter for the coding. @froggydoggyad123 for giving me the idea.
