This release improves support for multi-part books. Authors can now use heading markup on a trail page to denote the parts of a book. For example:
If the heading text starts with “Part:” (or “unPart:” for an unnumbered part), the typeset-book directive will treat this as a part heading. Books are currently the only document type for which parts are supported. For other types of document (reports and articles), headings on trail pages continue to be treated as section names.
Thanks to Crisses for identifying the need to improve support for multi-part books.