Menu on wrong Monitor

#include <QAction>
#include <QApplication>
#include <QMainWindow>
#include <QMenu>
#include <QToolBar>

int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
    QMainWindow w;

    auto menu = new QMenu();
    menu->addAction( "Menu Action 1" );

    auto action = new QAction();
    action->setText( "Test Action" );
    action->setMenu( menu );  

    auto toolbar = new QToolBar();
    toolbar->addAction( action );   

    w.addToolBar( Qt::ToolBarArea::LeftToolBarArea, toolbar );    

    w.show();
    return a.exec();
}