@tktech Very oddly, apparently nothing at all? Will have to investigate that further...
@tktech mastodon.social returns 'link: <https://mastodon.social/api/v1/timelines/public?max_id=109587048907649843>; rel="next", <https://mastodon.social/api/v1/timelines/public?min_id=109587049292283879>; rel="prev"', when I tried it now.