@mararm For interaction with AndStatus GNU Social is using protocol, borrowed from Twitter many years ago, when people didn't think about putting "activity streams” into real software yet. That protocol doesn't have ”favoriting activity ” also.
As we see, in order to compensate this shortage, GNUSocial developers invented a hack: a server really sends "favoriting activity” to AndStatus, but not in the machines understandable form (as modern protocols, e.g. in Pump.io, do) but as a normal post, only prepending it with words: ”User favorites something by...". I hope upcoming implementations will allow AndStatus understand user's actions correctly and clearly show you ONE post, having several "likes" by different users, and not several posts, looking suspiciously similar...
@gargron ;-)