*** `jekyll`: v3.5, not v4.x. Use `gem install jekyll --force --version 3.5.0` to force install of Jekyll 3.5.0.
*** `asciidoctor`: v1.5.6.2, not 1.5.7 or higher. Use `gem install asciidoctor --force --version 1.5.6.2`. NOTE: You must do this before installing `jekyll-asciidoc` or you'll get a version of Asciidoctor that we can't use yet.
See the additional documentation in `src/metadocs` for more information about how to edit files, build for releases, or modifying any Jekyll or PDF templates.