anchor.diff:                +footnote('hn-phrasing-content-model')
                 +footnote('p-phrasing-content-model')
                 +footnote('pre-phrasing-content-model')
  +              +footnote('legend-phrasing-content-model')
  +              +footnote('summary-phrasing-content-model')
               | An element with a #[dfn#phrasing-content-model Phrasing Content Model] may contain only Phrasing Content children. 
               small All text-level elements have the Phrasing Content Model unless otherwise specified.
             li
  
positive.code:               +footnote('address')
                +footnote('dt')
                +footnote('th')
              | The #[code address], #[code dt], and #[code th] elements may contain Flow Content except
              |  Sectioning Content, Heading Content, #[code header]s, and #[code footer]s.
      script(src="../bower_components/jquery/dist/jquery.js")
      script(src="https://cdn.mathjax.org/mathjax/latest/MathJax.js?config=TeX-AMS-MML_HTMLorMML,https://chharvey.github.io/chhlib/mathjax-localconfig.js")
      script(src="../core/scripts/global.js")
  
negative.code:               +footnote('figure-sectioning-root')
                +footnote('blockquote-sectioning-root')
                +footnote('td-sectioning-root')
                +footnote('fieldset-sectioning-root')
                +footnote('details-sectioning-root')
                +footnote('dialog-sectioning-root')
              | #[dfn Sectioning Roots] have their own outlines, but they are encapsulated,
              |  hidden from the Document Outline (#[abbr.c-Acro#document-outline(title="document outline") DO]).
            li
  