anchor.diff:  The new theme keys let you customize the font properties, text alignment, and item spacing of callout lists.
   The `callout-list` category includes the `margin-top-after-code` key that can control the top margin of callout lists that immediately follow a code block.
   
  -.*Notable fixes for callouts*
  +.*_Notable fixes for callouts_*
   * Callout numbers in a callout list stay with primary text when an item is advanced to the next page.
   * A sequence of two or more callouts separated by spaces in a code block are processed correctly.
   * The font family assigned to `conums` in the theme is applied to the callout numbers displayed in code blocks.
  
positive.code: 
  == Removed
  
  The following dependencies and deprecated features have been removed with the release of Asciidoctor PDF 2.0.0.
  
  * Support for Ruby < 2.7 and JRuby < 9.2 has been removed.
  * The `untitled` option has been removed; use the `notitle` option instead.
  
negative.code: [#breakable]
  == Breakable by default
  
  In Asciidoctor PDF {page-component-version}, the following blocks are breakable by default, which includes automatic anchor and caption orphan prevention:
  
  * Admonitions
  * Block images
  