Section 1.1, "Quick start", of the FDP primer only mentions docproj and subversion, but textproc/fop is also required if PDF output is desired, and not installed by default in the textproc/docproj metaport. This could be fixed by either changing the default options in textproc/docproj or adding a note to the documentation; since I've had no answer to my email linked above in 5 months, I'm going the latter route. Cc'ing doceng@ on bcr's advice.
A commit references this bug: Author: bcr Date: Mon Jun 15 16:29:35 UTC 2020 New revision: 54256 URL: https://svnweb.freebsd.org/changeset/doc/54256 Log: Add optional fop install step to generate PDF output. The textproc/fop is an optional package that can be installed to generate PDF output of our docs. It is not included in textproc/docproj by default and if not strictly required, but for those who want PDFs we describe how. While here, bump the copyright dates of the FDP primer. Thanks to Pau Amma for this change. PR: 247019 Submitted by: pauamma_gundo.com Reviewed by: debdrup, allanjude Approved by: allanjude, bcr Differential Revision: https://reviews.freebsd.org/D25170 Changes: head/en_US.ISO8859-1/books/fdp-primer/book.xml head/en_US.ISO8859-1/books/fdp-primer/overview/chapter.xml
I've committed your patch from the review. Thank you!