--- qtbase/src/widgets/widgets/qdockwidget_p.h	2016-06-10 09:48:56.000000000 +0300
+++ qtbase/src/widgets/widgets/qdockwidget_p.h	2016-09-19 11:53:01.443397100 +0300
@@ -105,6 +105,7 @@
 
 //    QMainWindow *findMainWindow(QWidget *widget) const;
     QRect undockedGeometry;
+    QSize undockedSize;
     QString fixedWindowTitle;
 
     bool mousePressEvent(QMouseEvent *event);