QGraphicsProxyWidget: cursor does not change shape when resizing a QHeaderView

When embedding a QTableWidget inside a QGraphicsView using QGraphicsProxyWidget, then it is possible to resize the width and hight of rows and columns, but the cursor shape does not change from arrow to split cursor. It remains an arrow cursor both when hovering the "splitter" and resizing the rows/columns.

Note :
QGraphicsProxyWidget must listen to QEvent::CursorChange its embedded widget and all widgets inside for it to work properly. In the proxy widget's event filter, the cursor can be set on the proxy widget. Either that, or we need to change QWidget::setCursor to propagate explicitly to the proxy widget (a better solution, but only fixable inside Qt).