Asciidoctor-pdf书签深度(Asciidoctor-pdf Bookmark Depth)

 有没有办法增加生成的pdf书签列表的深度？ 我指的是在诸如Adobe阅读器等阅读器中打开时的左侧导航书签面板。 看起来asciidoctor-pdf只能生成3级深度。 或asciidoc中的“===”深度。 
 
= title
== section 1
=== sub section 1
==== sub section a
==== sub section b
=== sub section 2
== section 2
 
 在上面的例子中，书签中缺少子节a和b。 

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.

原文：https://stackoverflow.com/questions/42096538