Markup block - Gen<None> - 31 - (0:0,0)
    Tag block - Gen<TagHelper> - 31 - (0:0,0) - p - ptaghelper
        StartTagAndEndTag - <p class=btn" bar="foo"<strong>
        class - NoQuotes
            Markup span - Gen<Markup> - [btn] - SpanEditHandler;Accepts:Any - (9:0,9) - Tokens:1
                HtmlTokenType.Text;[btn];
