Ah, interesting. The activitypub tag is configured to receive topics from another community vi the ActivityPub protocol (it’s a two-way sync, topics and replies on meta also go to the other community).
However, it looks like the plugin doesn’t pick a default category for the topics it creates. I am not sure if this is strictly a plugin issue or an issue with meta.
@tobiaseigen is there a site setting for “default category to pick when none is specified”? I see we have a default composer category but that’s not quite the same thing.