For me personally, footnotes are much better placed at the end of a text, rather than at the bottom of each page. Page-bottom footnotes awaken my inner completionist, which makes me not only read all of them, but jump between note point, note, and back again, severely breaking my reading flow.
Footnotes placed at the end of chapters or the whole book are completely stress-free. I completely forget about them soon after passing the note point, no matter how interesting it may have seemed, and rarely if ever remember to refer back.
Better
What I do both like and use are hyperlinks when I read text in browsers. Open lots of tabs while reading, then go through the tabs at some appropriate point and discover whatever fun treasures there may be.
Also decent
Pages and apps which gather footnotes and present them as popovers instead of jumping back and forth. Much better than on-page notes, but they always hit read- and usa-bility snags at one point or another.
Also not good
Wikipedia's footnote links. They never feel as if they bring me to the right points to feel clear and not break my flow. Neither when cliking the footnote, nor when clicking to jump back. Perhaps I am holding them wrong?