--- a/widget/PuppetWidget.cpp
+++ b/widget/PuppetWidget.cpp
@@ -224,17 +224,17 @@ PuppetWidget::Resize(double aWidth,
   return NS_OK;
 }
 
 nsresult
 PuppetWidget::ConfigureChildren(const nsTArray<Configuration>& aConfigurations)
 {
   for (uint32_t i = 0; i < aConfigurations.Length(); ++i) {
     const Configuration& configuration = aConfigurations[i];
-    PuppetWidget* w = static_cast<PuppetWidget*>(configuration.mChild);
+    PuppetWidget* w = static_cast<PuppetWidget*>(configuration.mChild.get());
     NS_ASSERTION(w->GetParent() == this,
                  "Configured widget is not a child");
     w->SetWindowClipRegion(configuration.mClipRegion, true);
     nsIntRect bounds;
     w->GetBounds(bounds);
     if (bounds.Size() != configuration.mBounds.Size()) {
       w->Resize(configuration.mBounds.x, configuration.mBounds.y,
                 configuration.mBounds.width, configuration.mBounds.height,

--- a/widget/android/nsWindow.cpp
+++ b/widget/android/nsWindow.cpp
@@ -275,17 +275,17 @@ nsWindow::Destroy(void)
 
     return NS_OK;
 }
 
 NS_IMETHODIMP
 nsWindow::ConfigureChildren(const nsTArray<nsIWidget::Configuration>& config)
 {
     for (uint32_t i = 0; i < config.Length(); ++i) {
-        nsWindow *childWin = (nsWindow*) config[i].mChild;
+        nsWindow *childWin = (nsWindow*) config[i].mChild.get();
         childWin->Resize(config[i].mBounds.x,
                          config[i].mBounds.y,
                          config[i].mBounds.width,
                          config[i].mBounds.height,
                          false);
     }
 
     return NS_OK;

--- a/widget/gtk/nsWindow.cpp
+++ b/widget/gtk/nsWindow.cpp
@@ -4124,17 +4124,17 @@ nsWindow::ConfigureChildren(const nsTArr
     // size information from a source other than our owner. Don't let our parent
     // update this information.
     if (mWindowType == eWindowType_plugin_ipc_chrome) {
       return NS_OK;
     }
 
     for (uint32_t i = 0; i < aConfigurations.Length(); ++i) {
         const Configuration& configuration = aConfigurations[i];
-        nsWindow* w = static_cast<nsWindow*>(configuration.mChild);
+        nsWindow* w = static_cast<nsWindow*>(configuration.mChild.get());
         NS_ASSERTION(w->GetParent() == this,
                      "Configured widget is not a child");
         w->SetWindowClipRegion(configuration.mClipRegion, true);
         if (w->mBounds.Size() != configuration.mBounds.Size()) {
             w->Resize(configuration.mBounds.x, configuration.mBounds.y,
                       configuration.mBounds.width, configuration.mBounds.height,
                       true);
         } else if (w->mBounds.TopLeft() != configuration.mBounds.TopLeft()) {

--- a/widget/nsIWidget.h
+++ b/widget/nsIWidget.h
@@ -1454,17 +1454,17 @@ class nsIWidget : public nsISupports {
      */
     virtual nsTransparencyMode GetTransparencyMode() = 0;
 
     /**
      * This represents a command to set the bounds and clip region of
      * a child widget.
      */
     struct Configuration {
-        nsIWidget* mChild;
+        nsCOMPtr<nsIWidget> mChild;
         uintptr_t mWindowID; // e10s specific, the unique plugin port id
         bool mVisible; // e10s specific, widget visibility
         nsIntRect mBounds;
         nsTArray<nsIntRect> mClipRegion;
     };
 
     /**
      * Sets the clip region of each mChild (which must actually be a child

--- a/widget/windows/nsWindow.cpp
+++ b/widget/windows/nsWindow.cpp
@@ -6350,17 +6350,17 @@ nsWindow::ConfigureChildren(const nsTArr
     return NS_OK;
   }
 
   // XXXroc we could use BeginDeferWindowPos/DeferWindowPos/EndDeferWindowPos
   // here, if that helps in some situations. So far I haven't seen a
   // need.
   for (uint32_t i = 0; i < aConfigurations.Length(); ++i) {
     const Configuration& configuration = aConfigurations[i];
-    nsWindow* w = static_cast<nsWindow*>(configuration.mChild);
+    nsWindow* w = static_cast<nsWindow*>(configuration.mChild.get());
     NS_ASSERTION(w->GetParent() == this,
                  "Configured widget is not a child");
     nsresult rv = w->SetWindowClipRegion(configuration.mClipRegion, true);
     NS_ENSURE_SUCCESS(rv, rv);
     nsIntRect bounds;
     w->GetBounds(bounds);
     if (bounds.Size() != configuration.mBounds.Size()) {
       w->Resize(configuration.mBounds.x, configuration.mBounds.y,