Index: /trunk/src/VBox/Frontends/VirtualBox/src/main.cpp
===================================================================
--- /trunk/src/VBox/Frontends/VirtualBox/src/main.cpp	(revision 56915)
+++ /trunk/src/VBox/Frontends/VirtualBox/src/main.cpp	(revision 56916)
@@ -372,4 +372,14 @@
         QApplication a(argc, argv);
 
+#ifdef Q_WS_X11
+        /* To avoid various Qt crashes
+         * when testing widget attributes or acquiring winIds
+         * we decided to make our widgets native under x11 hosts.
+         * Yes, we aware of note that alien widgets faster to draw
+         * but the only widget we need to be fast - viewport of VM
+         * was always native since we are using his id for 3d service needs. */
+        a.setAttribute(Qt::AA_NativeWindows);
+#endif /* Q_WS_X11 */
+
 #ifdef Q_WS_MAC
 # ifdef VBOX_GUI_WITH_HIDPI