--- a/content/html/content/src/nsHTMLDNSPrefetch.cpp
+++ b/content/html/content/src/nsHTMLDNSPrefetch.cpp
@@ -89,16 +89,20 @@ nsHTMLDNSPrefetch::Shutdown()
   NS_IF_RELEASE(sDNSListener);
   
   return NS_OK;
 }
 
 bool
 nsHTMLDNSPrefetch::IsAllowed (nsIDocument *aDocument)
 {
+  if (NS_IsAppOffline(aDocument->NodePrincipal())) {
+    return false;
+  }
+
   // There is no need to do prefetch on non UI scenarios such as XMLHttpRequest.
   return aDocument->IsDNSPrefetchAllowed() && aDocument->GetWindow();
 }
 
 nsresult
 nsHTMLDNSPrefetch::Prefetch(Link *aElement, uint16_t flags)
 {
   if (!(sInitialized && sPrefetches && sDNSService && sDNSListener))

--- a/dom/ipc/PBrowser.ipdl
+++ b/dom/ipc/PBrowser.ipdl
@@ -534,16 +534,21 @@ child:
     async RequestNotifyAfterRemotePaint();
 
     /**
      * Tell the child that the UI resolution changed for the containing
      * window.
      */
     UIResolutionChanged();
 
+    /**
+     * Tell the child of an app's offline status
+     */
+    AppOfflineStatus(uint32_t id, bool offline);
+
 /*
  * FIXME: write protocol!
 
 state LIVE:
     send LoadURL goto LIVE;
 //etc.
     send Destroy goto DYING;
 

--- a/dom/ipc/TabChild.cpp
+++ b/dom/ipc/TabChild.cpp
@@ -75,16 +75,17 @@
 #include "nsViewportInfo.h"
 #include "JavaScriptChild.h"
 #include "nsILoadContext.h"
 #include "ipc/nsGUIEventIPC.h"
 #include "mozilla/gfx/Matrix.h"
 #include "UnitTransforms.h"
 #include "ClientLayerManager.h"
 #include "LayersLogging.h"
+#include "nsIOService.h"
 
 #include "nsColorPickerProxy.h"
 
 #define BROWSER_ELEMENT_CHILD_SCRIPT \
     NS_LITERAL_STRING("chrome://global/content/BrowserElementChild.js")
 
 #define TABC_LOG(...)
 // #define TABC_LOG(...) printf_stderr("TABC: " __VA_ARGS__)
@@ -2567,16 +2568,28 @@ TabChild::RecvAsyncMessage(const nsStrin
       static_cast<nsFrameMessageManager*>(mTabChildGlobal->mMessageManager.get());
     CpowIdHolder cpows(Manager(), aCpows);
     mm->ReceiveMessage(static_cast<EventTarget*>(mTabChildGlobal),
                        aMessage, false, &cloneData, &cpows, aPrincipal, nullptr);
   }
   return true;
 }
 
+bool
+TabChild::RecvAppOfflineStatus(const uint32_t& aId, const bool& aOffline)
+{
+  // Instantiate the service to make sure gIOService is initialized
+  nsCOMPtr<nsIIOService> ioService = mozilla::services::GetIOService();
+  if (gIOService && ioService) {
+    gIOService->SetAppOfflineInternal(aId, aOffline ?
+      nsIAppOfflineInfo::OFFLINE : nsIAppOfflineInfo::ONLINE);
+  }
+  return true;
+}
+
 class UnloadScriptEvent : public nsRunnable
 {
 public:
   UnloadScriptEvent(TabChild* aTabChild, TabChildGlobal* aTabChildGlobal)
     : mTabChild(aTabChild), mTabChildGlobal(aTabChildGlobal)
   { }
 
   NS_IMETHOD Run()

--- a/dom/ipc/TabChild.h
+++ b/dom/ipc/TabChild.h
@@ -369,16 +369,18 @@ public:
     virtual bool RecvActivateFrameEvent(const nsString& aType, const bool& capture) MOZ_OVERRIDE;
     virtual bool RecvLoadRemoteScript(const nsString& aURL,
                                       const bool& aRunInGlobalScope) MOZ_OVERRIDE;
     virtual bool RecvAsyncMessage(const nsString& aMessage,
                                   const ClonedMessageData& aData,
                                   const InfallibleTArray<CpowEntry>& aCpows,
                                   const IPC::Principal& aPrincipal) MOZ_OVERRIDE;
 
+    virtual bool RecvAppOfflineStatus(const uint32_t& aId, const bool& aOffline) MOZ_OVERRIDE;
+
     virtual PDocumentRendererChild*
     AllocPDocumentRendererChild(const nsRect& documentRect, const gfx::Matrix& transform,
                                 const nsString& bgcolor,
                                 const uint32_t& renderFlags, const bool& flushLayout,
                                 const nsIntSize& renderSize) MOZ_OVERRIDE;
     virtual bool DeallocPDocumentRendererChild(PDocumentRendererChild* actor) MOZ_OVERRIDE;
     virtual bool RecvPDocumentRendererConstructor(PDocumentRendererChild* actor,
                                                   const nsRect& documentRect,

--- a/dom/ipc/TabParent.cpp
+++ b/dom/ipc/TabParent.cpp
@@ -235,16 +235,17 @@ TabParent::TabParent(nsIContentParent* a
   , mDPI(0)
   , mDefaultScale(0)
   , mShown(false)
   , mUpdatedDimensions(false)
   , mManager(aManager)
   , mMarkedDestroying(false)
   , mIsDestroyed(false)
   , mAppPackageFileDescriptorSent(false)
+  , mSendOfflineStatus(true)
   , mChromeFlags(aChromeFlags)
 {
   MOZ_ASSERT(aManager);
 }
 
 TabParent::~TabParent()
 {
 }
@@ -494,16 +495,24 @@ TabParent::LoadURL(nsIURI* aURI)
 
     if (!mShown) {
         NS_WARNING(nsPrintfCString("TabParent::LoadURL(%s) called before "
                                    "Show(). Ignoring LoadURL.\n",
                                    spec.get()).get());
         return;
     }
 
+    uint32_t appId = OwnOrContainingAppId();
+    if (mSendOfflineStatus && NS_IsAppOffline(appId)) {
+      // If the app is offline in the parent process
+      // pass that state to the child process as well
+      unused << SendAppOfflineStatus(appId, true);
+    }
+    mSendOfflineStatus = false;
+
     unused << SendLoadURL(spec);
 
     // If this app is a packaged app then we can speed startup by sending over
     // the file descriptor for the "application.zip" file that it will
     // invariably request. Only do this once.
     if (!mAppPackageFileDescriptorSent) {
         mAppPackageFileDescriptorSent = true;
 

--- a/dom/ipc/TabParent.h
+++ b/dom/ipc/TabParent.h
@@ -423,16 +423,20 @@ private:
     // managing PContent.
     bool mMarkedDestroying;
     // When true, the TabParent is invalid and we should not send IPC messages
     // anymore.
     bool mIsDestroyed;
     // Whether we have already sent a FileDescriptor for the app package.
     bool mAppPackageFileDescriptorSent;
 
+    // Whether we need to send the offline status to the TabChild
+    // This is true, until the first call of LoadURL
+    bool mSendOfflineStatus;
+
     uint32_t mChromeFlags;
 
     nsCOMPtr<nsILoadContext> mLoadContext;
 };
 
 } // namespace dom
 } // namespace mozilla