With a checkbox for whether or not the group shows up in the styling, in case we want private groups for some reason.
It would already be possible to do crazy CSS stuff with matching on article[data-user-id=6626], but that would be very annoying to do for every user in the group.
I’m not actually that experienced with CSS - is there actually a selector that would allow a forum to do that (set a background-image on the post) for everyone with a title?