The Link post format and some of the other post formats intentionally have their title hidden. That is the standard way of displaying such post formats. If you want to change that, you can certainly edit the CSS in a child theme. 🙂
Regarding footnotes: Those are currently hidden on the Post Pages because if you click a footnote link on a Post Page (with several other posts also being displayed), the footnote links won’t work (they won’t be able to figure out exactly which post in the list of posts the footnote belongs to). What would be necessary to make footnotes work on the Post Page would be to programmatically rewrite footnote links so that the contain an unique identifier, that identifies the post they belong to. There is a feature request open for that on GitHub. I recommend posting a comment over there so that you can stay updated with regards to that feature request.