anchor.diff:      '{{! the content, to provide tooltips for modified regions. }}'
       '{{{ regionContent }}}'
       '</div></div>'
  +    '<div>Footer</div>'
       r'''
       {{/ units }}
       <script lang="javascript">
  
positive.code:   font-weight: bold;
  }
  
  .code {
    left: 0.5em;
    /* Increase line height to make room for borders in non-nullable type
  
negative.code:    */
    line-height: 1.3;
    padding-left: 60px;
    position: inherit;
    top: 0.5em;
  }
  
  .regions {
  