This parses the guide section in the content.opf for text/start
references and jumps to this on first open of the book.
Currently, this behavior will be repeated in case the reader manually
jumps to Chapter 0 and then re-opens the book. IMO, this is an
acceptable edge case (for which I couldn't see a good fix other than to
drag a "first open" boolean around).
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Co-authored-by: Sam Davis <sam@sjd.co>
Co-authored-by: Dave Allie <dave@daveallie.com>
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