anchor.diff:      li Remove <code>a.self-link</code>
       li Remove <code>highlight</code> from <code>class</code> attribute
       li Remove <code>role</code> attribute (ex. <code>role=note</code>)
  -    li Remove “Allowed ARIA role attribute values:” and “Allowed ARIA state and property attributes:” (temporary)
  
positive.code:   h3 Modifications applied to W3C HTML 5.1
    ul
      li Replace “’” with “'”
      li Replace “Serializing” with “Serialising” in “The HTML syntax” and “The XHTML syntax”
      li Replace “Colors” with “Colours” in “Common infrastructure”
      li Replace “Plugin Content Handlers” with “Plugins” in “Common infrastructure”
      li Reorder “Links” in “The elements of HTML”
  
    h2 Q. Are HTMLs displayed in this site same as the specifications?
  
negative.code:     li <code>ruby</code>
      li <code>cite</code>
      li <code>iframe[seamless]</code>
      li <code>xml:base</code>
      li Table sorting model
      li <code>input[type="datetime-local"]</code> and <code>input[type="datetime"]</code>
      li Canvas 2D Context
  