I’m trying to figure out a way to hide posts. Not make the private or password-protected, available to anyone who has the URL, but just such that they don’t show up listed on the home page or elsewhere. I would use this for longer footnote-type additions to other posts. Ideally, I’d have an entire category (“footnotes”) that doesn’t show anywhere, and in which the posts don’t show anywhere, either. Is this possible by adding CSS? I use the Escutcheon theme.
Your Escutcheon theme is currently set to show all your latest posts/blogs on your home page. If you don’t want some posts to show here, I would suggest you use pages for this information. These pages won’t show unless you add them in your menu or somewhere else.
You can find more info about pages vs posts in this link: https://en.support.wordpress.com/post-vs-page/