TreeTable showing empty fileds after scrolling


I’m having problems using TreeTable: in fact does not always show all data fields after scrolling.

I used a HierarchicalContainer where:
‘Codice’,‘Gruppo’,‘RPN’ Properties are Strings
‘Titolo’ Property is Label
As shown in attached image ‘Titolo’ field value is not always correctly rendered.

It seems similar to issue described in ticket #6160

I tried using refreshRowCache() method but nothing changed.

Does anyone know how to solve this problem?

Thanks in advance