It would be good to have a small Instant Messenger in the Spotify Desktop Application. It would be nice to check with someone on the songs that you have just shared with them. Also, it can serve as a general purpose messenger.
The messenger can be very limited without advanced features like File Sharing etc... (to avoid copyrighted content sharing)
The messenger can just pop up if I click on someone's name on the right hand section of the application (the pane that shows Person X listened to this song ....)
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