Counting Iz Hrd
I can't see a second reply there either.
On desktop, it expands to show the first 20 posts in the topic before then triggering the next batch of posts and, well, breaking.
That's what you get for using a No
Actually, that seems to be happening consistently in that thread, but it isn't an off-by-one error. It's an off-by-a-factor-of-two error...
edit: but only those 3 posts... going back a few pages, all the previous ones appear to have correct reply counts.