Is there a way to increase the generated pdf bookmark list's depth? I am referring to the left navigation bookmark panel when opening in readers such as Adobe reader. It appears that asciidoctor-pdf only generates to level 3 depth. or "===" depth in asciidoc.
= title
== section 1
=== sub section 1
==== sub section a
==== sub section b
=== sub section 2
== section 2
In the above example, sub section a and b would be missing from the bookmarks.