Index: /trunk/src/VBox/Frontends/VirtualBox/src/extradata/UIExtraDataManager.cpp
===================================================================
--- /trunk/src/VBox/Frontends/VirtualBox/src/extradata/UIExtraDataManager.cpp	(revision 76163)
+++ /trunk/src/VBox/Frontends/VirtualBox/src/extradata/UIExtraDataManager.cpp	(revision 76164)
@@ -3709,5 +3709,6 @@
 {
     /* Not for primary screen: */
-    AssertReturn(uScreenIndex > 0, true);
+    if (uScreenIndex == 0)
+        return true;
 
     /* Compose corresponding key: */
@@ -3721,5 +3722,6 @@
 {
     /* Not for primary screen: */
-    AssertReturnVoid(uScreenIndex > 0);
+    if (uScreenIndex == 0)
+        return;
 
     /* Compose corresponding key: */
Index: /trunk/src/VBox/Frontends/VirtualBox/src/runtime/UIMachineView.cpp
===================================================================
--- /trunk/src/VBox/Frontends/VirtualBox/src/runtime/UIMachineView.cpp	(revision 76163)
+++ /trunk/src/VBox/Frontends/VirtualBox/src/runtime/UIMachineView.cpp	(revision 76164)
@@ -319,4 +319,7 @@
             (int)screenId(), size.width(), size.height()));
 
+    /* Record the hint to extra data, needed for guests using VMSVGA: */
+    storeGuestSizeHint(size);
+
     /* If auto-mount of guest-screens (auto-pilot) enabled: */
     if (gEDataManager->autoMountGuestScreensEnabled(vboxGlobal().managedVMUuid()))
@@ -434,5 +437,11 @@
     /* If we are in normal or scaled mode and if GA are active,
      * remember the guest-screen size to be able to restore it when necessary: */
-    if (!isFullscreenOrSeamless() && uisession()->isGuestSupportsGraphics())
+    /* As machines with Linux/Solaris and VMSVGA are not able to tell us
+     * whether a resize was due to the system or user interaction we currently
+     * do not store hints for these systems except when we explicitly send them
+     * ourselves.  Windows guests should use VBoxVGA controllers, not VMSVGA. */
+    if (   !isFullscreenOrSeamless()
+        && uisession()->isGuestSupportsGraphics()
+        && (machine().GetGraphicsControllerType() != KGraphicsControllerType_VMSVGA))
         storeGuestSizeHint(QSize(iWidth, iHeight));
 
Index: /trunk/src/VBox/Frontends/VirtualBox/src/runtime/UISession.cpp
===================================================================
--- /trunk/src/VBox/Frontends/VirtualBox/src/runtime/UISession.cpp	(revision 76163)
+++ /trunk/src/VBox/Frontends/VirtualBox/src/runtime/UISession.cpp	(revision 76164)
@@ -2061,4 +2061,7 @@
     /* Remember 'actual' (host-desire) visibility status: */
     m_monitorVisibilityVectorHostDesires[(int)uScreenId] = fIsMonitorVisible;
+
+    /* And remember the request in extra data for guests with VMSVGA: */
+    gEDataManager->setLastGuestScreenVisibilityStatus(uScreenId, fIsMonitorVisible, vboxGlobal().managedVMUuid());
 }
 
@@ -2080,5 +2083,7 @@
     m_monitorVisibilityVector[(int)uScreenId] = fIsMonitorVisible;
     /* Remember 'desired' visibility status: */
-    gEDataManager->setLastGuestScreenVisibilityStatus(uScreenId, fIsMonitorVisible, vboxGlobal().managedVMUuid());
+    /* See note in UIMachineView::sltHandleNotifyChange() regarding the graphics controller check. */
+    if (machine().GetGraphicsControllerType() != KGraphicsControllerType_VMSVGA)
+        gEDataManager->setLastGuestScreenVisibilityStatus(uScreenId, fIsMonitorVisible, vboxGlobal().managedVMUuid());
 
     /* Make sure action-pool knows guest-screen visibility status: */