Thread view

I especially like the folding all posts on the page apart from the last. Not sure about users closing their own thread. It sounds very reasonable but sometimes an equally good or even better (subjective) response comes a few days later and it would be a pity if those responses could not be posted, even if only for the benefit of other readers of the thread.

Marking the thread as problem solved (ideally in the title) might be useful, but I agree that should not mean the thread is closed for further discussion.
Threads are often useful to others beyond the OP, and can be referred to years later (the reason the loss of the historical data in DPR will be missed).
Sometime the solution that worked for the OP, can involve steps that could damage equipment or even the photographer, having the ability to point these out & suggest refinements is good. But having the title changed will hopefully reduce duplicate answers - 150 posts saying 'use a tripod' become pretty pointless :)

Would it be an idea?
The thing is that a reply goes always to the end an not just below the specific post

This looks real good. A really great idea.

Very good suggestions, for me too 👍🏻

Tree view was the main, defining advantage of the DPReview forum for me. I can't believe it's the only forum software that I've found that uses that approach. Every single other forum I belong to is harder to follow for that specific reason. Tree view + putting the subject in subthreads made scanning a thread 100 times easier than trying to read every post in flat view, figure out who was responding to whom, and finding responses to a subthread that interested me.

i cant believe it as well as all my database management systems i designed nearly 40 years ago on Mac where all button/tree structure designed . give it a few months and the issue will be fixed.