diff --git a/content/base/public/nsIFrameLoader.idl b/content/base/public/nsIFrameLoader.idl
index 0d1bc55a182..db6f49a9def 100644
--- a/content/base/public/nsIFrameLoader.idl
+++ b/content/base/public/nsIFrameLoader.idl
@@ -141,7 +141,7 @@ interface nsIContentViewManager : nsISupports
   readonly attribute nsIContentView rootContentView;
 };
 
-[scriptable, uuid(13c512d6-fba0-402a-9244-fe7941c43965)]
+[scriptable, uuid(12905a29-4246-475a-81d4-fc389197df02)]
 interface nsIFrameLoader : nsISupports
 {
   /**
@@ -187,6 +187,12 @@ interface nsIFrameLoader : nsISupports
    */
   void activateRemoteFrame();
 
+  /**
+   * Deactivate remote frame.
+   * Throws an exception with non-remote frames.
+   */
+  void deactivateRemoteFrame();
+
   /**
    * @see nsIDOMWindowUtils sendMouseEvent.
    */
diff --git a/content/base/src/nsFrameLoader.cpp b/content/base/src/nsFrameLoader.cpp
index 08218d521f5..7ab32bfe550 100644
--- a/content/base/src/nsFrameLoader.cpp
+++ b/content/base/src/nsFrameLoader.cpp
@@ -1771,6 +1771,15 @@ nsFrameLoader::ActivateRemoteFrame() {
   return NS_ERROR_UNEXPECTED;
 }
 
+NS_IMETHODIMP
+nsFrameLoader::DeactivateRemoteFrame() {
+  if (mRemoteBrowser) {
+    mRemoteBrowser->Deactivate();
+    return NS_OK;
+  }
+  return NS_ERROR_UNEXPECTED;
+}
+
 NS_IMETHODIMP
 nsFrameLoader::SendCrossProcessMouseEvent(const nsAString& aType,
                                           float aX,
diff --git a/dom/base/nsFocusManager.cpp b/dom/base/nsFocusManager.cpp
index f57189c8fb9..2023b84732c 100644
--- a/dom/base/nsFocusManager.cpp
+++ b/dom/base/nsFocusManager.cpp
@@ -34,6 +34,8 @@
  *
  * ***** END LICENSE BLOCK ***** */
 
+#include "mozilla/dom/TabParent.h"
+
 #include "nsFocusManager.h"
 
 #include "nsIInterfaceRequestor.h"
@@ -1531,14 +1533,14 @@ nsFocusManager::Blur(nsPIDOMWindow* aWindowToClear,
       NotifyFocusStateChange(content, shouldShowFocusRing, PR_FALSE);
     }
 
-    // if an object/plug-in is being blurred, move the system focus to the
-    // parent window, otherwise events will still get fired at the plugin.
+    // if an object/plug-in/remote browser is being blurred, move the system focus
+    // to the parent window, otherwise events will still get fired at the plugin.
     // But don't do this if we are blurring due to the window being lowered,
     // otherwise, the parent window can get raised again.
-    if (mActiveWindow && aAdjustWidgets) {
+    if (mActiveWindow) {
       nsIFrame* contentFrame = content->GetPrimaryFrame();
       nsIObjectFrame* objectFrame = do_QueryFrame(contentFrame);
-      if (objectFrame) {
+      if (aAdjustWidgets && objectFrame) {
         // note that the presshell's widget is being retrieved here, not the one
         // for the object frame.
         nsIViewManager* vm = presShell->GetViewManager();
@@ -1549,6 +1551,15 @@ nsFocusManager::Blur(nsPIDOMWindow* aWindowToClear,
             widget->SetFocus(PR_FALSE);
         }
       }
+
+      // if the object being blurred is a remote browser, deactivate remote content
+      TabParent* remote = GetRemoteForContent(content);
+      if (remote) {
+        remote->Deactivate();
+  #ifdef DEBUG_FOCUS
+      printf("*Remote browser deactivated\n");
+  #endif
+      }
     }
   }
 
@@ -1746,12 +1757,21 @@ nsFocusManager::Focus(nsPIDOMWindow* aWindow,
 
       NotifyFocusStateChange(aContent, aWindow->ShouldShowFocusRing(), PR_TRUE);
 
-      // if this is an object/plug-in, focus the plugin's widget.  Note that we might
+      // if this is an object/plug-in/remote browser, focus its widget.  Note that we might
       // no longer be in the same document, due to the events we fired above when
       // aIsNewDocument.
-      if (aAdjustWidgets && presShell->GetDocument() == aContent->GetDocument()) {
-        if (objectFrameWidget)
+      if (presShell->GetDocument() == aContent->GetDocument()) {
+        if (aAdjustWidgets && objectFrameWidget)
           objectFrameWidget->SetFocus(PR_FALSE);
+
+        // if the object being focused is a remote browser, activate remote content
+        TabParent* remote = GetRemoteForContent(aContent);
+        if (remote) {
+          remote->Activate();
+#ifdef DEBUG_FOCUS
+          printf("*Remote browser activated\n");
+#endif
+        }
       }
 
       PRUint32 reason = GetFocusMoveReason(aFlags);
@@ -2948,6 +2968,28 @@ nsFocusManager::GetRootForFocus(nsPIDOMWindow* aWindow,
   return rootElement;
 }
 
+TabParent*
+nsFocusManager::GetRemoteForContent(nsIContent* aContent) {
+  if (!aContent ||
+      aContent->Tag() != nsGkAtoms::browser ||
+      !aContent->IsXUL() ||
+      !aContent->AttrValueIs(kNameSpaceID_None, nsGkAtoms::Remote,
+                             nsGkAtoms::_true, eIgnoreCase))
+    return nsnull;
+
+  nsCOMPtr<nsIFrameLoaderOwner> loaderOwner = do_QueryInterface(aContent);
+  if (!loaderOwner)
+    return nsnull;
+
+  nsRefPtr<nsFrameLoader> frameLoader = loaderOwner->GetFrameLoader();
+  if (!frameLoader)
+    return nsnull;
+
+  PBrowserParent* remoteBrowser = frameLoader->GetRemoteBrowser();
+  TabParent* remote = static_cast<TabParent*>(remoteBrowser);
+  return remote;
+}
+
 void
 nsFocusManager::GetLastDocShell(nsIDocShellTreeItem* aItem,
                                 nsIDocShellTreeItem** aResult)
diff --git a/dom/base/nsFocusManager.h b/dom/base/nsFocusManager.h
index 737187b9540..5aa0c718075 100644
--- a/dom/base/nsFocusManager.h
+++ b/dom/base/nsFocusManager.h
@@ -49,6 +49,13 @@
 
 class nsIDocShellTreeItem;
 class nsPIDOMWindow;
+
+namespace mozilla {
+namespace dom {
+  class TabParent;
+}
+}
+
 struct nsDelayedBlurOrFocusEvent;
 
 /**
@@ -424,6 +431,12 @@ protected:
                               PRBool aIsForDocNavigation,
                               PRBool aCheckVisibility);
 
+  /**
+   * Get the TabParent associated with aContent if it is a remote browser,
+   * or null in all other cases.
+   */
+  mozilla::dom::TabParent* GetRemoteForContent(nsIContent* aContent);
+
   /**
    * Get the last docshell child of aItem and return it in aResult.
    */
diff --git a/dom/ipc/PBrowser.ipdl b/dom/ipc/PBrowser.ipdl
index 0be8db40034..abcb2c7b9f2 100644
--- a/dom/ipc/PBrowser.ipdl
+++ b/dom/ipc/PBrowser.ipdl
@@ -241,6 +241,8 @@ child:
      */
     Activate();
 
+    Deactivate();
+
     /**
      * @see nsIDOMWindowUtils sendMouseEvent.
      */
diff --git a/dom/ipc/TabChild.cpp b/dom/ipc/TabChild.cpp
index 140e2adc6b6..d414468672d 100644
--- a/dom/ipc/TabChild.cpp
+++ b/dom/ipc/TabChild.cpp
@@ -556,6 +556,13 @@ TabChild::RecvActivate()
   return true;
 }
 
+bool TabChild::RecvDeactivate()
+{
+  nsCOMPtr<nsIWebBrowserFocus> browser = do_QueryInterface(mWebNav);
+  browser->Deactivate();
+  return true;
+}
+
 bool
 TabChild::RecvMouseEvent(const nsString& aType,
                          const float&    aX,
diff --git a/dom/ipc/TabChild.h b/dom/ipc/TabChild.h
index f840dcd6608..dc6462db358 100644
--- a/dom/ipc/TabChild.h
+++ b/dom/ipc/TabChild.h
@@ -180,6 +180,7 @@ public:
     virtual bool RecvShow(const nsIntSize& size);
     virtual bool RecvMove(const nsIntSize& size);
     virtual bool RecvActivate();
+    virtual bool RecvDeactivate();
     virtual bool RecvMouseEvent(const nsString& aType,
                                 const float&    aX,
                                 const float&    aY,
diff --git a/dom/ipc/TabParent.cpp b/dom/ipc/TabParent.cpp
index 1cddde7eba9..e6bd3bb0b4f 100644
--- a/dom/ipc/TabParent.cpp
+++ b/dom/ipc/TabParent.cpp
@@ -219,6 +219,12 @@ TabParent::Activate()
     unused << SendActivate();
 }
 
+void
+TabParent::Deactivate()
+{
+  unused << SendDeactivate();
+}
+
 NS_IMETHODIMP
 TabParent::Init(nsIDOMWindow *window)
 {
diff --git a/dom/ipc/TabParent.h b/dom/ipc/TabParent.h
index 4d130d07048..5671acd4a30 100644
--- a/dom/ipc/TabParent.h
+++ b/dom/ipc/TabParent.h
@@ -127,6 +127,7 @@ public:
     void Show(const nsIntSize& size);
     void Move(const nsIntSize& size);
     void Activate();
+    void Deactivate();
     void SendMouseEvent(const nsAString& aType, float aX, float aY,
                         PRInt32 aButton, PRInt32 aClickCount,
                         PRInt32 aModifiers, PRBool aIgnoreRootScrollFrame);