Markup block - Gen<None> - 18 - (0:0,0)
    Tag block - Gen<TagHelper> - 18 - (0:0,0) - p - ptaghelper
        StartTagAndEndTag - <p> ... </p>
        Markup span - Gen<Markup> - [Hello World] - SpanEditHandler;Accepts:Any - (3:0,3) - Tokens:3
            HtmlTokenType.Text;[Hello];
            HtmlTokenType.WhiteSpace;[ ];
            HtmlTokenType.Text;[World];
