Rules for when users appear in meta data below first post

Hi folks - just a question that I can’t see documented anywhere, what are the rules for when users appear below the first post, eg:


This is appearing on some posts and I can’t tell if it’s triggered by # of users in a topic or # of posts in a topic (or something else entirely). Ideally I’d like it to show on every post but I can’t find settings to customise the behaviour.

It’s both

Thanks Moin! Super interesting feature - is there a way to change the default behaviour, eg: show participant avatars when there is >2 posts?