height 100% forces repeating and/or cut-off text.

[dvschultz]

Without section {height: 100%;} (where the section element wraps all text):

With section {height: 100%;}:

(notice the cropped text at the top. Not shown here is that 75% of the text here was on the previous page as well.)

(These are Kindle Previewer screens, but they accurately reflect the issues on Kindle Fires as well).

[dvschultz]

I’d initially attributed this to the body element, but after more research it looks like it applies to an element wrapping the text.