anchor.diff:    ///
     /// Escapes single quotes (`'`) but not double quotes (`"`),
     /// and escapes `<` and `>` characters because they are not allowed
  -  /// in strict XHTML attributes
  +  /// in strict XHTML attributes.
     static const HtmlEscapeMode sqAttribute =
         HtmlEscapeMode._('attribute', true, false, true, false);
   
     /// Escaping mode for text going into HTML element content.
     ///
     /// The escaping only works for elements with normal HTML content,
  -  /// and not for, for example, script or style element content,
  +  /// and not, for example, for script or style element content,
     /// which require escapes matching their particular content syntax.
     ///
     /// Escapes `<` and `>` characters.
  
positive.code: /// Escaping `>` (greater than) isn't necessary, but the result is often
  /// found to be easier to read if greater-than is also escaped whenever
  /// less-than is.
  class HtmlEscape extends Converter<String, String> {
    /// The [HtmlEscapeMode] used by the converter.
    final HtmlEscapeMode mode;
  
negative.code: 
  /// HTML escape modes.
  ///
  /// Allows specifying a mode for HTML escaping that depends on the context
  /// where the escaped result is going to be used.
  /// The relevant contexts are:
  ///
  