I cannot find a Script. I used to have it a long time ago, but I cannot remember the name. It's the one that tells you when the person you are talking to closes their chat window.
Such script doesn't exist at the moment, because the Messenger network connection cannot clearly indicate when a conversation is closed. Nevertheless, the add-on 'Messenger Discovery Live' tries to sniff the network stream, but from my own tests with it, I discovered that the closed-notes were mostly much too late, or didn't show at all.
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