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So, I used gtalk a lot with Pidgin (and later Empathy) before its 'death' or 'transition' to Google Hangouts. I can use it as a chrome extension but Windows users have a standalone application, which is a lot better.
Or even a telepathy plugin - even if the plugin isn't FOSS, is such a plugin feasible, so it would work with Empathy and KDE Telepathy, for example?
Fundamental Axiom of the Universe (aka Murphy's Law): Whatever can go wrong, will go wrong.
First Digital Deduction: Nothing obeys Murphy's Law so well as computers.
Second Digital Deduction: Everything go wrong at least once.
Third Digital Deduction: Things go wrong even when there's absolutely no possibility of anything go wrong.
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XMPP made it possible for third-party clients to hook into Google Talk back in the day. But after the merge with Hangouts, XMPP support was dropped. Google has signaled through its actions that it's not interested in opening up Hangouts to third-party integrations, so I doubt we'll ever see something like this--or, if we do, it'll be a clandestine effort at constant risk of being blocked.
Prove me wrong, Google! Prooove meee wroooong!
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