It got merged with another. The second is is currently #8 on the frontpage. https://news.ycombinator.com/item?id=38519012 "comments moved to https://news.ycombinator.com/item?id=38517550, which has that article, which presumably gives more background."

Got it, thanks!

This is weird, however: the upvotes should have migrated as well then, no?

To the total of ~1260 as of now.

And an automatic redirect would be good. I wouldn't be surprised if merging is the moderator manually editing the database, I don't think it's very sophisticated.

or a submenu [other mentions] or [similar] something like that...

The explanation is in this comment thread:

https://news.ycombinator.com/item?id=38519228

Now now, Mr Lakomen.