Unclear whether this is a bug or a feature request — please treat accordingly. Either way, it’s a minor thing.
prioritize_username_in_ux = true, when hovering an avatar on the list of recent posters, it uses the person’s name (not username). On a forum where username is what most people go by, showing the username would be more helpful on that context.
prioritize_username_in_ux be followed on avatar tooltips (on latest posters list)?