Posting the last forum post in a page redirects you to the next, nonexistent page which then overflows and takes you to a broken Page 1

[FIareon]

Describe the bug
When posting the last post in a page on a forum thread, you are taken to a page that doesn't exist automatically. I assume the site is trying to take you to the next one, but it overflows and shits itself since the next page hasn't been created yet.

To Reproduce
Steps to reproduce the behavior:

1. Go to any forum thread with 14 posts on the last page, or fill it up yourself until it's at the 14th post in a page
2. Type anything and send the 15th (and last) forum post for the page. You will be taken to a null page
3. You are now on a page that doesn't exist

Expected behavior
Posting the 15th forum post simply keeps you on the same page. Posting a 16th would take you to the next page which is created and put your latest post there.

Screenshots

Smartphone (please complete the following information):

• OS: Android 10
• Browser Chrome
• Version 131

Additional context
This has consistently happened when posting casually. It could get annoying.

[wescopeland]

This is occurring likely due to previous posts in the thread being made by users who are not yet forum-authorized.