Originally Posted by
mp.syd
Oh how quickly the conspiracy theories and wild ass speculation begins...
It's a bug in the mobile template - specifically it's not correctly encoding the URL for the later pages on some threads. So when it's used, it's close enough to work out which thread to show but not the right page / post.
Those reading along might have noted I used 'some threads' and be wondering which ones. I'm glad you asked, the magic (or not so magic) is when the thread title starts with an emoji or icon. It handles titles with emojis, in the middle correctly. It's not related to the thread creator and appears to be OS / browser agnostic (I don't have all the combinations handy to check).
As pointed out, the full site works fine. So the workaround is to look at those threads from the full site.
mp
PS - Admin, if you want more details of what I found PM me.