QWindow::resize() doesn't propagate the new size to the backing QWidget if the main eventloop hasn't started yet

 
diff --git a/src/widgets/kernel/qwidgetwindow.cpp b/src/widgets/kernel/qwidgetwindow.cpp
index 35a526e..d417e41 100644
--- a/src/widgets/kernel/qwidgetwindow.cpp
+++ b/src/widgets/kernel/qwidgetwindow.cpp
@@ -551,6 +551,13 @@ void QWidgetWindow::updateGeometry()
 
     const QMargins margins = frameMargins();
 
+    if (geometry().x() != m_widget->data->crect.x() ||
+        geometry().y() != m_widget->data->crect.y())
+        m_widget->setAttribute(Qt::WA_Moved);
+    if (geometry().width()  != m_widget->data->crect.width() ||
+        geometry().height() != m_widget->data->crect.height())
+        m_widget->setAttribute(Qt::WA_Resized);
+
     m_widget->data->crect = geometry();
     QTLWExtra *te = m_widget->d_func()->topData();
     te->posIncludesFrame= false;