When I click on 'A HN post with negative points – how?' from the HN homepage (currently ranked 12 for me), it goes to https://news.ycombinator.com/item?id=48104663 instead of https://news.ycombinator.com/item?id=48106316 (I found the latter via google search for the title string)

I suspect the same is happening for some others too, based on the comments on that article.

Bizarre!

Update: 2 minutes later and the link from the hn home page now correctly leads to: https://news.ycombinator.com/item?id=48106316

Never seen that happen before.

This post you are commenting on (*6316) is a link post that points to the other one (*4663)

The normal behavior for link posts in HN is that the title takes you to the link address, not to the post address.

To enter the post address, you need to hit the "discuss"/"x comments" button.

So, what you describe is HN working as expected AFAICT, it's just a bit counterintuitive because it's an HN post linking to another, which is uncommon

Pointers are hard

This post has been added as a link, instead of a comment one. Then when you click on it you go the linked page.

LGTM