Is there an open source forum-CMS like phpBB that works like imgur but can be self hosted? Discourse would be the only candidate I can think of and I don't thin

Is there an open source forum-CMS like phpBB that works like imgur but can be self hosted? Discourse would be the only candidate I can think of and I don't think I could teach my welder buddy to admin it for his welding group (he doesn't like FB).