It seems, with searchable electronic documents, the glossary has,
mostly, gone the way of the dodo bird. IMO the glossary is only good for letting people know what's in the book if they don't already know what to search for. Instead of direct links, the electronic reader/app should just allow a long (or hard) tap to bring up that word in a search function.... BTW, that function is available in Marvin - it will not only find the word in the book, but it can search the internet for that word to get definitions, references, examples, etc.
Multiple, identical, footnotes also should no longer be necessary - unless the book is some kind of reference/technical work. Most people read from the beginning to the end. If they care about the footnote reference, they would click on it when they come across the first instance, and then not need it on subsequent instances - presumably they would have learned the reference the first time... (yes, I know, that might be expecting too much of some people
)