Not a definite answer by any measure, but pg started linking to https://news https://news... instead of http://news http://news... sometime around 11 years ago:

Not a definite answer by any measure, but pg started linking to https://news https://news... instead of http://news http://news... sometime around 11 years ago: https://hn.algolia.com/?dateRange=all&page=0&prefix=true&query=by%3Apg%20news.ycombinator.com&sort=byDate&type=comment https://hn.algolia.com/?dateRange=all&page=0&prefix=true&que... Before that, all http links instead.