QTreeView + setColumnWidth + StyleSheet + QStackedWidget

Good morning,
since I installed the QT version 6.6.1/6.5.4 I have encountered anomalous behavior.

If I use a QStackedWidget, a QTreeView, use stylesheets and try to set the size of the tree view columns, this happens:

1) I set the stylesheet in main.cpp;
I create the MainWindow.

With this declaration the columns are sized to 100 and my settings are not respected.

2) If I remove the style sheet in main.cpp everything works correctly;

3) leaving the style sheet, to make everything work I have to:
in the MyWidget class, to the QTreeView, I have to pass the stacked widget as parent and not this;
in the MainWindow class I have to create the container, call setCentralWidget, create the MyClass instance and pass the stacked widget contained in the container as a parent.

I attach a small example project.
In the MainWindow.cpp file activate the define NO_ERROR to make the program work correctly.

In Qt version 6.6.0 everything worked correctly.

I tried the one suggested in BUG120418 but it doesn't work.