anchor.diff:    @override
     bool onMatch(md.InlineParser parser, Match match) {
       var url = match[1];
  -    var text = md.escapeHtml(url).replaceFirst(_hide_schemes, '');
  +    var text = htmlEscape.convert(url).replaceFirst(_hide_schemes, '');
       var anchor = new md.Element.text('a', text);
       anchor.attributes['href'] = url;
       parser.addNode(anchor);
  
positive.code:   "video",
    "wbr"
  ];
  final RegExp nonHTML =
      new RegExp("</?(?!(${validHtmlTags.join("|")})[> ])\\w+[> ]");
  
  
negative.code: // warn about them.
  // Covers anything with leading digits/symbols, empty string, weird punctuation, spaces.
  final RegExp notARealDocReference = new RegExp(r'''(^[^\w]|^[\d]|[,"'/]|^$)''');
  
  final HtmlEscape htmlEscape = const HtmlEscape(HtmlEscapeMode.ELEMENT);
  
  final List<md.InlineSyntax> _markdown_syntaxes = [
    new _InlineCodeSyntax(),
  