BreOl72: That's an old problem. It's going on for years.
idbeholdME: Hmmm, ran into this for the first time. Must have been lucky I guess.
I know about the issue where being the first to comment on a news thread results in an error (the thread still gets created), and I know deleted posts can also cause some paging issues, but there we no deleted posts in the one I linked.
Good to know this won't be getting fixed any time soon I guess :P
EDIT: Now seems to be working fine. 2nd page shows up with the last post on 30 posts per page, even though no posts have been added. Is it just some caching issues? Just seems strange to have fixed itself without any action.
Yeah, it usually happens more when there's high traffic on the site or on threads with lots of posts, but a brief delay may be common in nearly every thread. Sometimes someone else posting as well will make the new page get generated properly, but often it's just a matter of time, which can range between a couple of minutes and several, maybe even more sometimes. What may seem stranger is when the post appears right after you post it, but if you reload the thread that page, and therefore the post, doesn't show up anymore until said time passes.