anchor.diff:      {ok, Ts} = scan(Css),
       case z_css_parser:parse(Ts) of
           {error, {Line, z_css_parser, Error}} ->
  -            {error, {Line, iolist_to_binary(Error)}};
  +            {error, {Line, unicode:characters_to_binary(Error)}};
           {ok, {stylesheet, Charset, Import, Rules}} ->
               Charset1 = sanitize_charset(Charset),
               Import1 = sanitize_import(Import),
               Rules1 = [ sanitize_rule(R) || R <- Rules ],
  -            {ok, iolist_to_binary([
  +            {ok, unicode:characters_to_binary([
                   serialize_charset(Charset1),
                   serialize_import(Import1),
                   [ serialize_rule(R) || R <- Rules1 ]
  
positive.code:     case z_css_parser:parse(Ts) of
          {ok, {stylesheet, no_charset, no_import, [{rule, _Sel, Declarations}]}} ->
              SanitizedDs = [ sanitize_declaration(D) || D <- Declarations ],
              Ts1 = iolist_to_binary([ serialize_declaration(D) || D <- SanitizedDs ]),
              {ok, binary:replace(Ts1, <<"\n">>, <<" ">>, [global])};
          {error, {Line, z_css_parser, Error}} ->
              {error, {Line, iolist_to_binary(Error)}}
      end.
  
  
  
negative.code: 
  sanitize_string([Quot|S]) when Quot =:= $"; Quot =:= $' ->
      S1 = lists:sublist(S, length(S)-1),
      [ $", z_html:escape_check(z_html:strip(unicode:characters_to_binary(S1))), $"].
  
  
  %%% -------------------------------------------------------- 
  