1   QQuickDeliveryAgentPrivate::handleMouseEvent           qquickdeliveryagent.cpp    1764
2   QQuickOverlay::eventFilter                             qquickoverlay.cpp          569 
3   QCoreApplicationPrivate::sendThroughObjectEventFilters qcoreapplication.cpp       1255
4   QCoreApplicationPrivate::notify_helper                 qcoreapplication.cpp       1284
5   doNotify                                               qcoreapplication.cpp       1219
6   QCoreApplication::notify                               qcoreapplication.cpp       1202
7   QGuiApplication::notify                                qguiapplication.cpp        2076
8   QCoreApplication::notifyInternal2                      qcoreapplication.cpp       1118
9   QCoreApplication::sendSpontaneousEvent                 qcoreapplication.cpp       1572
10  QGuiApplicationPrivate::processMouseEvent              qguiapplication.cpp        2485
11  QGuiApplicationPrivate::processWindowSystemEvent       qguiapplication.cpp        2212
12  QWindowSystemInterface::sendWindowSystemEvents         qwindowsysteminterface.cpp 1113
13  xcbSourceDispatch                                      qxcbeventdispatcher.cpp    57  

bool QWindow::event(QEvent *ev)
{
    Q_D(QWindow);
    switch (ev->type()) {
    case QEvent::MouseMove:
        mouseMoveEvent(static_cast<QMouseEvent*>(ev));
        break;

    case QEvent::MouseButtonPress: {
        auto *me = static_cast<QMouseEvent*>(ev);
        mousePressEvent(me);
        if (!ev->isAccepted())
            d->maybeSynthesizeContextMenuEvent(me);