I got a repro.
I went to thread Trump calls for nuclear rearmament which had some unread posts for me along with prior mod deletions.
I scroll up a few posts and the Back button appears (as expected). I can tap on that button until my finger breaks but it never jumps to a later post (not expected).
ETA same problem in The food in "Final Fantasy XV" looks amazing which I know for a fact also had mod deletions.
