Posted by abelsromero on Dec 05, 2018; 8:16am
URL: https://discuss.asciidoctor.org/Adding-Words-to-Title-Causes-Errors-tp6627p6632.html

The issue comes from title underline that uses Markdown syntax.
It should be the same length as the title text.

Most of the book already uses normal Asciidoctor syntax for titles (= prefix), I'd recommend replacing it to avoid this kind of issues.

Btw, I run the book with v 1.5.6.1 and 1.5.8 successfully, I also recommend to update to the last version, just change the Gemfile.