Markup block - Gen<None> - 33 - (0:0,0)
    Tag block - Gen<None> - 5 - (0:0,0)
        Markup span - Gen<Markup> - [<foo>] - SpanEditHandler;Accepts:None - (0:0,0) - Tokens:3
            SyntaxKind.OpenAngle;[<];
            SyntaxKind.Text;[foo];
            SyntaxKind.CloseAngle;[>];
    Markup span - Gen<Markup> - [<!DOCTYPE foo bar baz>] - SpanEditHandler;Accepts:None - (5:0,5) - Tokens:10
        SyntaxKind.OpenAngle;[<];
        SyntaxKind.Bang;[!];
        SyntaxKind.Text;[DOCTYPE];
        SyntaxKind.Whitespace;[ ];
        SyntaxKind.Text;[foo];
        SyntaxKind.Whitespace;[ ];
        SyntaxKind.Text;[bar];
        SyntaxKind.Whitespace;[ ];
        SyntaxKind.Text;[baz];
        SyntaxKind.CloseAngle;[>];
    Tag block - Gen<None> - 6 - (27:0,27)
        Markup span - Gen<Markup> - [</foo>] - SpanEditHandler;Accepts:None - (27:0,27) - Tokens:4
            SyntaxKind.OpenAngle;[<];
            SyntaxKind.ForwardSlash;[/];
            SyntaxKind.Text;[foo];
            SyntaxKind.CloseAngle;[>];
