Mate I think you are talking about a plugin no a script.... and that plugin's name was Stuffplug NG... this plugin no longer exist... but there is a new version of it called
Stuffplug 3 (in beta stage) but isn't a plugin of Messenger Plus! anymore... is a standalone program... the only problem is that the function you wanna use isn't available anymore... cause isn't posible... visit this
page to know why (search the forums there is already a thread of it)...
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