I continue to get a lot of reads on Medium for a brief (but well-researched) tantrum I threw 5 years ago about a design change they made to their marginal notes, which are a much better solution to the same problem. Imho. Not sure how well that could work in an ebook, mind, but then I'm kinda ok with how ebooks handle them atm. https://medium.com/@owenblacker/marginal-notes-on-medium-268b3f727e6d