I think this is right, where "most recent post" is chosen from both comments and submissions. Looking at top of the https://news.ycombinator.com/newest https:/

I think this is right, where "most recent post" is chosen from both comments and submissions. Looking at top of the https://news.ycombinator.com/newest https://news.ycombinator.com/newest page illustrates this pattern. Almost every timestamp there ends with a dot, except for the cases where the submitter commented on their own submission, in which case that comment has the dot. For example: https://news.ycombinator.com/item?id=25198319 https://news.ycombinator.com/item?id=25198319.