for a short time, he was monitoring the referral header and made his website display an offensive message if you clicked the link from HN.

HN's mods then edited links to his domain so they would emit the referral header, and he responded by implementing a browser exploit to detect if certain HN URLs were in your browser history.

In any case, I apologize for using the wrong wording.

IIRC it was if you link directly to the Asahi Linux website then a bit of javascript picks up the HN referrer and blocks viewing the page.