I'm exporting my book to a reflowable EPUB. I specifie EPUB3.0, and Placement "Inside a Pop-up".
If I view the exported epub in Kindle Previewer 3, the footnotes are, in fact, available inside a pop-up when I click. But they are also placed a little later in the text, where they look to the reader like part of the normal text flow, which is wrong. They are in two places.
Needless to say, I only want the popup, not both places.
In Adobe Digital Editions, the footnote reference is shown in the text, but when I click, it sends me to text later in the document flow, where many of the footnotes are ganged up together. As in the Kindle Previewer, they look like part of the normal text flow, which is wrong.
The popup has to be able to pull from somewhere, and that's usually a list of notes appended to the end of the document. There is no way that I know of to make that set of notes invisible. It's just a facet of how hard it is to put "page notes" in an essentially pageless document.
Don't worry about what ADE does. It's a badly flawed reader for EPUB. If you want to proof and validate EPUB on its own, use Thorium Reader, which is about as vanilla and standard-based as readers get. (Almost no two readers handle docs the same way; you have to pick your battles and optimizing docs for Thorium serves the biggest audience.)
Consider also putting your footnotes inline, following the paragraph they're referencing. With a little graceful formatting, it's not any more obtrusive than paper footnotes, and solves all the technical/reader problems.
I didn't know about Thorium. I thought Kindle was the most popular reader. Who is the audience for Thorium, and where do they buy content? I was self-publishing on Amazon KDP. Is there another outlet I should consider?
Unfortunately, I'm using the "indented text with different style" paradigm already, for another purpose. I guess I could just include the footnotes as parenthetical text in the main document.
Reflowable epub is very painful. Attractive image sizing and positioning seems hopeless. If I make it look good one one one device, it looks terrible on the next, and page-breaks magically appear and disappear. There's a lot of mystery in the positioning, and some things that sure look like bugs. Is this known to be a path filled with minefields?
Kindle is only for Kindle... it's a closed doc, reader and sales system. The doc format has evolved over time and was originally based on MOBI, but now is a more proprietary format.
EPUB is a universal, open-standard format. Unfortunately, the standard is so open and an enforcement entity so absent that it's become a huge headache. Every tool and every e-book seller has their own variant file and reader quirks and it's impossible to have a truly universal file, at least if you want to maintain any semblance of formatting or structure. (They will all display "plain text" about the same.)
Thorium is a reader re/developed by an entity that does care about the EPUB standard and doesn't have the desire to implement new, cool features on their own. So Thorium (evolved from Readium) is about as close to a standard, standards-compliant reader as exists. If your doc works and looks right there... frankly, any problems on other readers are those other readers' fault.
While fixed-page EPUB is "easy," it's also a lousy use of the tech and IMVHO largely obsolete and a misuse of the medium. (You want fixed pages? Use PDF.)
Reflowable EPUB is not an easy medium to master, and the amount of outdated, misguided and just plain wrong information and advice out there is titanic. After a number of years and many attempts to engage the various communities at a professional level, I've given up and written it all off. (I can tell stories...)
If you want to do professional EPUB and Kindle, using a modern, standards-based approach and starting with ID... see below. 🙂
Well, this is interesting. I downloaded Thorium, and my reflowable book looks great! All the images are where I want them, all the sizing and spacing is just right. Unlike the Kindle Previewer. So that brings up the question of how to provide a reflowable version for Thorium and a fixed version for Kindle.
You usually need to optimize docs for each end format. It's not that hard, you just use different specs (typically font size and spacing) for each, and there are some other differences (Kindle honors page breaks; EPUB does not, etc.)
You can maintain two different ID docs, or one doc and find a way to switch the style sets, or use one ID doc and two different CSS files for export.
Move away from FXL. It's worth the effort.
I could make two versions (Kindle vs. Thorium). How will people obtain the Thorium version to read? Where do people purchase content to read in Thorium? They can't do it in Amazon, can they?
BTW: Thorium does the correct thing with footnote popups.
There are many repository/sales portals for EPUB books. I rarely do them except for direct distribution from my website, or a client's.
EPUB in general is not dependent on a closed sales/reader/format cycle. EPUB is just a file; get it to your reader and you can read it.
Is there a block of footnontes at the end in Thorium? Can't recall if I've ever checked the details.