I did a mockup of an imageboard-like thread UX adapted to the bonfire UI, and I like it pretty much, because it addresses some issues I had since some time.
Here a draft:
( In this mockup, I imagined a user in the process of replying to few comments, quoting them on the create activity form in the upper-left sidebar )
Things I like at a first glance:
- Consistency with the other pages layout (sidebar + main content)
- The user has just 1 place to publish / reply to a discussion (the create activity form on the left sidebar), instead of showing multiple forms under each reply, this is quite great for accessibility.
- The user can reply to multiple comments at once (mind-blowing XD )
- Flat layout is easier to deal with, but at the same time users can navigate complexity and dig into nested threads (I think it can work well mixed with how @aschrijver was pointing out, about how discourse manages to show inline / nested replies in a flat UX
Here a draft of an expanded comment:
@swrup I’d appreciate your feedback, if I’m missing something relevant or getting something wrong 
Question:
- Do we introduce compatibility issues with the rest of federated platforms if we mention posts rather than users in our threads ? ( This should not be a blocker imo, but something to ponder )