I remember seeing this once, but given that it's so sporadic, I think it's a browser rendering bug, probably dependent on where it decides to start rendering the page. Not much we can do about it in that case.
Well that was that exact thread which you can see in the screenshot I attached to my first post.
Anyway @work on chrome I wasn't able to reproduce it. I haven't try to see if it was still there on my home computer but as It wasn't appearing every time (though everytime for the same) hard to say, especially with the long list of new posts, that thread get down to the deep sea