Markup block - Gen<None> - 17 - (0:0,0)
    Tag block - Gen<None> - 5 - (0:0,0)
        Markup span - Gen<Markup> - [<foo>] - SpanEditHandler;Accepts:Any - (0:0,0) - Symbols:3
            HtmlSymbolType.OpenAngle;[<];
            HtmlSymbolType.Text;[foo];
            HtmlSymbolType.CloseAngle;[>];
    Markup span - Gen<Markup> - [${bar}] - SpanEditHandler;Accepts:Any - (5:0,5) - Symbols:1
        HtmlSymbolType.Text;[${bar}];
    Tag block - Gen<None> - 6 - (11:0,11)
        Markup span - Gen<Markup> - [</foo>] - SpanEditHandler;Accepts:Any - (11:0,11) - Symbols:4
            HtmlSymbolType.OpenAngle;[<];
            HtmlSymbolType.ForwardSlash;[/];
            HtmlSymbolType.Text;[foo];
            HtmlSymbolType.CloseAngle;[>];
