@dansup I'm not sure what their f/oss record has to do w/anything. It's all going to be about their behavior, the culture - hell I'll presume they won't inject ads in feeds.
& I would argue the prudent thing for small-instance admins to do is domain-block pre-emptively.
Here's why: We know what Facebook culture is like. We know where Barcelona users will be coming from. Blocking THE domain IS REVERSABLE once they've demonstrated the culture behaves in a way that doesn't harm small instances.