@GeoffR: That might be it, feeding it to Mantano leads it to try to open it as an epub3 (which fails spectacularly, FWIW)

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That said, I still (mostly) don't see anything cut-off, except for the very edge of the italic g on the left.
What I do see is stuff cut-off from the top/bottom, with some fonts/line-spacing combo, but that's on every kind of kepub (with or without the book-inner/book-columns divs), and might be related to my extreme lack of margins, and/or the fact that I only patched for the left/right padding (although that would only apply to stuff w/ book-inner divs)?
EDIT: Although I guess that's probably a question more related to full-screen mode/the patches than this, since you pretty much answered my original question about why those kepubs weren't getting the book-inner treatment

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