startRant
{
Heavily foot/end-noted EBOOKS are a PITA. The concept of poop-ups [sic] doesn't work for 'serious' biographies and history texts which have significant quantities of notes.
I'm one of those who actually read them - avidly, for there's often more to be learnt from the notes than from the main body. The notion that note 123 can stand isolated from note 124 is absolute nonsense. For it is often the case that there will be two notes for the same passage of main text that contain alternative interpretations of the same event - the reader wants to see them together on the same page/viewport/monitor/whatever.
I sometimes resort to extracting the back of a book into a separate epub so I can read the notes etc on my phone and the main text on my tablet or ereader - just as often I throw my hands up and call my local owner operated bookshop and they get me a paper edition.
}
endRant
BR