QTreeView read only columns can not be selected.

Behavior Change from Qt5 to Qt6. If an item is read only in Qt5, that item was selectable and background color was able to change. But with Qt6 this is not possible. This leads a gui in very odd look. 

if it is considered that this behavior is right in Qt6, i.e. read only item should not be selected then it would be nice to have some way with qss to change the background color.

Attached simple example shows this behavior if compare with Qt5 and Qt6.