Problems following FDT Primer

[Dennis Friedrichsen]

Hello,

I am interested in becoming involved in submitting fixes for
documentation.  Long-time user and I've written a couple PRs in the past.

I'm trying to follow the setup instructions here:
https://docs.freebsd.org/en/books/fdp-primer/
(specifically the Quick Start)

I have a FreeBSD 12.2 fresh install.  I installed the required packages in
step 1. (Also did the optional packages in step 2).  I ran the git clone.
Then I tried to build the documentation and ran into this error:

------------------------

denny at freebsd12dot2doc:~/src/freebsd/doc/documentation % make

---------------------------------------------------------------

Building the documentation

---------------------------------------------------------------

/usr/local/bin/python3.7 ./tools/books-toc-parts-creator.py -l
en,es,pt-br,de,ja,zh-cn,zh-tw,ru,el,hu,it,mn,nl,pl,fr

/usr/local/bin/python3.7 ./tools/books-toc-creator.py -l
en,es,pt-br,de,ja,zh-cn,zh-tw,ru,el,hu,it,mn,nl,pl,fr

/usr/local/bin/python3.7 ./tools/books-toc-figures-creator.py -l
en,es,pt-br,de,ja,zh-cn,zh-tw,ru,el,hu,it,mn,nl,pl,fr

/usr/local/bin/python3.7 ./tools/books-toc-tables-creator.py -l
en,es,pt-br,de,ja,zh-cn,zh-tw,ru,el,hu,it,mn,nl,pl,fr

/usr/local/bin/python3.7 ./tools/books-toc-examples-creator.py -l
en,es,pt-br,de,ja,zh-cn,zh-tw,ru,el,hu,it,mn,nl,pl,fr

/usr/local/bin/hugo --minify

Start building sites …

*ERROR* 2021/01/31 09:27:23 Unsupported asciidoctor extension was passed
in. Extension `../shared/lib/man-macro.rb` ignored.

------------------

Any help or nudge in the right direction is appreciated.  Not sure if I'm
doing something wrong or maybe just missing a package.

Thank you,
Dennis

-- 
Dennis R. Friedrichsen