How to sync chats in Facebook chat through windows / tabs

Question

Sometimes during a chat, if I send a chat message to a friend in one window and switch to another window / tab in which facebook is open (and, of course, the chat window is open), my msg will automatically appear there.

Similarly, if friends ping you, ping goes to all facebook / windows loaded with windows / tabs. You do not want heavy parts, but how facebook does it.

Answer 1

Here's a blogpost on a facebook theme: https://www.facebook.com/note.php?note_id=14218138919

What you want to know is most likely described in this section:

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