Must be an issue with the site itself when viewed in Firefox on Windows; I've run into the same thing every time someone shares it here on HN. I even disabled uBO thinking that might be the cause, but the behavior didn't change. Eventually, I just gave up trying to access it.

Honestly, it's been disruptive enough that I'm considering adding the site to a personal blocklist, just to avoid running into it again. In the few times it's happened, the only way to recover was force-closing the browser, or waiting an excruciating amount of time and with a poorly responding browser try to close the tab.