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