diff --git a/content/base/test/test_child_process_shutdown_message.html b/content/base/test/test_child_process_shutdown_message.html
index dfebea910c74..40d5c7f6bea2 100644
--- a/content/base/test/test_child_process_shutdown_message.html
+++ b/content/base/test/test_child_process_shutdown_message.html
@@ -112,10 +112,6 @@ function setUp() {
   SpecialPowers.setBoolPref("dom.ipc.browser_frames.oop_by_default", true);
   SpecialPowers.addPermission("browser", true, window.document);
   SpecialPowers.addPermission("embed-apps", true, window.document);
-
-  // TODO: remove in bug 820712
-  SpecialPowers.setBoolPref("network.disable.ipc.security", true);
-
   runNextTest();
 }
 
@@ -140,10 +136,6 @@ function makeKillTest(isApp) function testKill() {
 function tearDown() {
   SpecialPowers.clearUserPref("dom.mozBrowserFramesEnabled");
   SpecialPowers.clearUserPref("dom.ipc.browser_frames.oop_by_default");
-
-  // TODO: remove in bug 820712
-  SpecialPowers.clearUserPref("network.disable.ipc.security");
-
   SimpleTest.finish();
 }
 
diff --git a/content/xul/templates/src/crashtests/crashtests.list b/content/xul/templates/src/crashtests/crashtests.list
index fbc33ba1675c..6ffd2e9ec7c8 100644
--- a/content/xul/templates/src/crashtests/crashtests.list
+++ b/content/xul/templates/src/crashtests/crashtests.list
@@ -1,7 +1,7 @@
 load 257752-1-recursion.xul
 load 329335-1.xul
 load 329884-1.xul
-skip-if(winWidget||browserIsRemote) HTTP load 330010-1.xul # bugs 742455 and 823470
+skip-if(winWidget) HTTP load 330010-1.xul # bug 742455
 skip-if(winWidget) load 330012-1.xul # bug 742455
 skip-if(winWidget) load 397148-1.xul # bug 742455
 load 404346-1.xul
diff --git a/docshell/base/LoadContext.cpp b/docshell/base/LoadContext.cpp
index 7bf55a466590..6861ecac3d61 100644
--- a/docshell/base/LoadContext.cpp
+++ b/docshell/base/LoadContext.cpp
@@ -8,12 +8,22 @@
 #include "nsIScriptSecurityManager.h"
 #include "nsServiceManagerUtils.h"
 #include "nsContentUtils.h"
-#include "mozIApplication.h"
 
 namespace mozilla {
 
 NS_IMPL_ISUPPORTS1(LoadContext, nsILoadContext);
 
+LoadContext::LoadContext(const IPC::SerializedLoadContext& aToCopy,
+                         nsIDOMElement* aTopFrameElemenet)
+  : mIsNotNull(aToCopy.mIsNotNull)
+  , mIsContent(aToCopy.mIsContent)
+  , mUsePrivateBrowsing(aToCopy.mUsePrivateBrowsing)
+  , mIsInBrowserElement(aToCopy.mIsInBrowserElement)
+  , mAppId(aToCopy.mAppId)
+  , mTopFrameElement(do_GetWeakReference(aTopFrameElemenet))
+{}
+
+
 //-----------------------------------------------------------------------------
 // LoadContext::nsILoadContext
 //-----------------------------------------------------------------------------
diff --git a/docshell/base/LoadContext.h b/docshell/base/LoadContext.h
index c1ba521b9bbd..29961ca44ac7 100644
--- a/docshell/base/LoadContext.h
+++ b/docshell/base/LoadContext.h
@@ -10,9 +10,6 @@
 #include "SerializedLoadContext.h"
 #include "mozilla/Attributes.h"
 #include "nsWeakReference.h"
-#include "nsIDOMElement.h"
-
-class mozIApplication;
 
 namespace mozilla {
 
@@ -32,19 +29,17 @@ public:
   NS_DECL_ISUPPORTS
   NS_DECL_NSILOADCONTEXT
 
-  // AppId/inBrowser arguments override those in SerializedLoadContext provided
-  // by child process.
-  LoadContext(const IPC::SerializedLoadContext& aToCopy,
-              nsIDOMElement* aTopFrameElement,
-              uint32_t aAppId, bool aInBrowser)
+  LoadContext(const IPC::SerializedLoadContext& aToCopy)
     : mIsNotNull(aToCopy.mIsNotNull)
     , mIsContent(aToCopy.mIsContent)
     , mUsePrivateBrowsing(aToCopy.mUsePrivateBrowsing)
-    , mIsInBrowserElement(aInBrowser)
-    , mAppId(aAppId)
-    , mTopFrameElement(do_GetWeakReference(aTopFrameElement))
+    , mIsInBrowserElement(aToCopy.mIsInBrowserElement)
+    , mAppId(aToCopy.mAppId)
   {}
 
+  LoadContext(const IPC::SerializedLoadContext& aToCopy,
+              nsIDOMElement* aTopFrameElemenet);
+
 private:
   bool          mIsNotNull;
   bool          mIsContent;
diff --git a/dom/browser-element/mochitest/browserElementTestHelpers.js b/dom/browser-element/mochitest/browserElementTestHelpers.js
index 4d9b1e56d461..356e8f0f92ff 100644
--- a/dom/browser-element/mochitest/browserElementTestHelpers.js
+++ b/dom/browser-element/mochitest/browserElementTestHelpers.js
@@ -65,14 +65,6 @@ const browserElementTestHelpers = {
     return this._setBoolPref("dom.ipc.browser_frames.oop_by_default", value);
   },
 
-  getIPCSecurityDisabledPref: function() {
-    return this._getBoolPref("network.disable.ipc.security");
-  },
-
-  setIPCSecurityDisabledPref: function(value) {
-    return this._setBoolPref("network.disable.ipc.security", value);
-  },
-
   getPageThumbsEnabledPref: function() {
     return this._getBoolPref('browser.pageThumbs.enabled');
   },
@@ -102,7 +94,6 @@ const browserElementTestHelpers = {
     this.setOOPDisabledPref(this.origOOPDisabledPref);
     this.setOOPByDefaultPref(this.origOOPByDefaultPref);
     this.setPageThumbsEnabledPref(this.origPageThumbsEnabledPref);
-    this.setIPCSecurityDisabledPref(this.origIPCSecurityPref);
     this.removeAllTempPermissions();
   },
 
@@ -110,7 +101,6 @@ const browserElementTestHelpers = {
   'origOOPDisabledPref': null,
   'origOOPByDefaultPref': null,
   'origPageThumbsEnabledPref': null,
-  'origIPCSecurityPref': null,
   'tempPermissions': [],
 
   // Some basically-empty pages from different domains you can load.
@@ -132,7 +122,6 @@ browserElementTestHelpers.origEnabledPref = browserElementTestHelpers.getEnabled
 browserElementTestHelpers.origOOPDisabledPref = browserElementTestHelpers.getOOPDisabledPref();
 browserElementTestHelpers.origOOPByDefaultPref = browserElementTestHelpers.getOOPByDefaultPref();
 browserElementTestHelpers.origPageThumbsEnabledPref = browserElementTestHelpers.getPageThumbsEnabledPref();
-browserElementTestHelpers.origIPCSecurityPref = browserElementTestHelpers.getIPCSecurityDisabledPref();
 
 // Disable tab view; it seriously messes us up.
 browserElementTestHelpers.setPageThumbsEnabledPref(false);
@@ -144,10 +133,6 @@ var oop = location.pathname.indexOf('_inproc_') == -1;
 browserElementTestHelpers.setOOPByDefaultPref(oop);
 browserElementTestHelpers.setOOPDisabledPref(false);
 
-// Disable the networking security checks; our test harness just tests browser elements
-// without sticking them in apps, and the security checks dislike that.
-browserElementTestHelpers.setIPCSecurityDisabledPref(true);
-
 addEventListener('unload', function() {
   browserElementTestHelpers.restoreOriginalPrefs();
 });
diff --git a/dom/devicestorage/ipc/test_ipc.html b/dom/devicestorage/ipc/test_ipc.html
index 1366f54dd27b..f0836eacd35a 100644
--- a/dom/devicestorage/ipc/test_ipc.html
+++ b/dom/devicestorage/ipc/test_ipc.html
@@ -153,9 +153,6 @@
           ["device.storage.testing", true],
           ["device.storage.prompt.testing", true],
 
-          // TODO: remove this as part of bug 820712
-          ["network.disable.ipc.security", true],
-
           ["dom.ipc.browser_frames.oop_by_default", true],
           ["dom.mozBrowserFramesEnabled", true],
           ["browser.pageThumbs.enabled", false]
diff --git a/dom/indexedDB/ipc/test_ipc.html b/dom/indexedDB/ipc/test_ipc.html
index fe4e0c722640..7cb1971aaf72 100644
--- a/dom/indexedDB/ipc/test_ipc.html
+++ b/dom/indexedDB/ipc/test_ipc.html
@@ -168,9 +168,6 @@
       SpecialPowers.addPermission("browser", true, document);
       SpecialPowers.pushPrefEnv({
         "set": [
-          // TODO: remove this as part of bug 820712
-          ["network.disable.ipc.security", true],
-
           ["dom.ipc.browser_frames.oop_by_default", true],
           ["dom.mozBrowserFramesEnabled", true]
         ]
diff --git a/dom/indexedDB/test/file_app_isolation.js b/dom/indexedDB/test/file_app_isolation.js
index 704288f7b260..514fb5824b65 100644
--- a/dom/indexedDB/test/file_app_isolation.js
+++ b/dom/indexedDB/test/file_app_isolation.js
@@ -159,10 +159,5 @@ if (!SpecialPowers.isMainProcess()) {
   todo(false, "We should make this work on content process");
   SimpleTest.finish();
 } else {
-  // TODO: remove unsetting network.disable.ipc.security as part of bug 820712
-  SpecialPowers.pushPrefEnv({
-    "set": [
-      ["network.disable.ipc.security", true],
-    ]
-  }, startTest);
+  startTest();
 }
diff --git a/dom/ipc/PBrowser.ipdl b/dom/ipc/PBrowser.ipdl
index a7270b93d557..7ccc34c952b6 100644
--- a/dom/ipc/PBrowser.ipdl
+++ b/dom/ipc/PBrowser.ipdl
@@ -216,6 +216,8 @@ parent:
      *   URI of the manifest to fetch, the application cache group ID
      * @param documentURI
      *   URI of the document that referred the manifest
+     * @param clientID
+     *   The group cache version identifier to use
      * @param stickDocument
      *   True if the update was initiated by a document load that referred
      *   a manifest.
@@ -233,6 +235,7 @@ parent:
      *   has already been cached (stickDocument=false).
      */
     POfflineCacheUpdate(URIParams manifestURI, URIParams documentURI,
+                        bool isInBrowserElement, uint32_t appId,
                         bool stickDocument);
 
     sync PIndexedDB(nsCString asciiOrigin)
diff --git a/dom/ipc/TabChild.cpp b/dom/ipc/TabChild.cpp
index eb480234d384..03fe4aa97ecc 100644
--- a/dom/ipc/TabChild.cpp
+++ b/dom/ipc/TabChild.cpp
@@ -1576,6 +1576,8 @@ TabChild::RecvActivateFrameEvent(const nsString& aType, const bool& capture)
 POfflineCacheUpdateChild*
 TabChild::AllocPOfflineCacheUpdate(const URIParams& manifestURI,
                                    const URIParams& documentURI,
+                                   const bool& isInBrowserElement,
+                                   const uint32_t& appId,
                                    const bool& stickDocument)
 {
   NS_RUNTIMEABORT("unused");
diff --git a/dom/ipc/TabChild.h b/dom/ipc/TabChild.h
index e565c1f1ceb8..3e76ee766aaa 100644
--- a/dom/ipc/TabChild.h
+++ b/dom/ipc/TabChild.h
@@ -277,6 +277,8 @@ public:
     virtual POfflineCacheUpdateChild* AllocPOfflineCacheUpdate(
             const URIParams& manifestURI,
             const URIParams& documentURI,
+            const bool& isInBrowserElement,
+            const uint32_t& appId,
             const bool& stickDocument);
     virtual bool DeallocPOfflineCacheUpdate(POfflineCacheUpdateChild* offlineCacheUpdate);
 
diff --git a/dom/ipc/TabParent.cpp b/dom/ipc/TabParent.cpp
index 3a490b06084a..3e445f3d950f 100644
--- a/dom/ipc/TabParent.cpp
+++ b/dom/ipc/TabParent.cpp
@@ -1132,13 +1132,15 @@ TabParent::DeallocPRenderFrame(PRenderFrameParent* aFrame)
 mozilla::docshell::POfflineCacheUpdateParent*
 TabParent::AllocPOfflineCacheUpdate(const URIParams& aManifestURI,
                                     const URIParams& aDocumentURI,
+                                    const bool& isInBrowserElement,
+                                    const uint32_t& appId,
                                     const bool& stickDocument)
 {
   nsRefPtr<mozilla::docshell::OfflineCacheUpdateParent> update =
-    new mozilla::docshell::OfflineCacheUpdateParent(OwnOrContainingAppId(),
-                                                    IsBrowserElement());
+    new mozilla::docshell::OfflineCacheUpdateParent();
 
-  nsresult rv = update->Schedule(aManifestURI, aDocumentURI, stickDocument);
+  nsresult rv = update->Schedule(aManifestURI, aDocumentURI,
+                                 isInBrowserElement, appId, stickDocument);
   if (NS_FAILED(rv))
     return nullptr;
 
diff --git a/dom/ipc/TabParent.h b/dom/ipc/TabParent.h
index bd640e3c9b7d..c44528fc8f70 100644
--- a/dom/ipc/TabParent.h
+++ b/dom/ipc/TabParent.h
@@ -191,6 +191,8 @@ public:
     virtual POfflineCacheUpdateParent* AllocPOfflineCacheUpdate(
             const URIParams& aManifestURI,
             const URIParams& aDocumentURI,
+            const bool& isInBrowserElement,
+            const uint32_t& appId,
             const bool& stickDocument);
     virtual bool DeallocPOfflineCacheUpdate(POfflineCacheUpdateParent* actor);
 
diff --git a/modules/libpref/src/init/all.js b/modules/libpref/src/init/all.js
index cd6f4a10a1ff..f3680aa1e1cf 100644
--- a/modules/libpref/src/init/all.js
+++ b/modules/libpref/src/init/all.js
@@ -773,9 +773,6 @@ pref("security.fileuri.strict_origin_policy", true);
 // the results
 pref("network.allow-experiments", true);
 
-// Turn off interprocess security checks. Needed to run xpcshell tests.
-pref("network.disable.ipc.security", false);
-
 // Default action for unlisted external protocol handlers
 pref("network.protocol-handler.external-default", true);      // OK to load
 pref("network.protocol-handler.warn-external-default", true); // warn before load
diff --git a/netwerk/cookie/CookieServiceChild.cpp b/netwerk/cookie/CookieServiceChild.cpp
index d0e88c578103..a20b33bff158 100644
--- a/netwerk/cookie/CookieServiceChild.cpp
+++ b/netwerk/cookie/CookieServiceChild.cpp
@@ -4,14 +4,12 @@
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 #include "mozilla/net/CookieServiceChild.h"
-#include "mozilla/dom/TabChild.h"
+
 #include "mozilla/ipc/URIUtils.h"
 #include "mozilla/net/NeckoChild.h"
 #include "nsIURI.h"
 #include "nsIPrefService.h"
 #include "nsIPrefBranch.h"
-#include "nsITabChild.h"
-#include "nsNetUtil.h"
 
 using namespace mozilla::ipc;
 
@@ -117,19 +115,10 @@ CookieServiceChild::GetCookieStringInternal(nsIURI *aHostURI,
   URIParams uriParams;
   SerializeURI(aHostURI, uriParams);
 
-  nsCOMPtr<nsITabChild> iTabChild;
-  mozilla::dom::TabChild* tabChild = nullptr;
-  if (aChannel) {
-    NS_QueryNotificationCallbacks(aChannel, iTabChild);
-    if (iTabChild) {
-      tabChild = static_cast<mozilla::dom::TabChild*>(iTabChild.get());
-    }
-  }
-
   // Synchronously call the parent.
   nsAutoCString result;
   SendGetCookieString(uriParams, !!isForeign, aFromHttp,
-                      IPC::SerializedLoadContext(aChannel), tabChild, &result);
+                      IPC::SerializedLoadContext(aChannel), &result);
   if (!result.IsEmpty())
     *aCookieString = ToNewCString(result);
 
@@ -159,18 +148,9 @@ CookieServiceChild::SetCookieStringInternal(nsIURI *aHostURI,
   URIParams uriParams;
   SerializeURI(aHostURI, uriParams);
 
-  nsCOMPtr<nsITabChild> iTabChild;
-  mozilla::dom::TabChild* tabChild = nullptr;
-  if (aChannel) {
-    NS_QueryNotificationCallbacks(aChannel, iTabChild);
-    if (iTabChild) {
-      tabChild = static_cast<mozilla::dom::TabChild*>(iTabChild.get());
-    }
-  }
-
   // Synchronously call the parent.
   SendSetCookieString(uriParams, !!isForeign, cookieString, serverTime,
-                      aFromHttp, IPC::SerializedLoadContext(aChannel), tabChild);
+                      aFromHttp, IPC::SerializedLoadContext(aChannel));
   return NS_OK;
 }
 
diff --git a/netwerk/cookie/CookieServiceParent.cpp b/netwerk/cookie/CookieServiceParent.cpp
index ef9655a69c80..90cb528574f6 100644
--- a/netwerk/cookie/CookieServiceParent.cpp
+++ b/netwerk/cookie/CookieServiceParent.cpp
@@ -4,44 +4,32 @@
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 #include "mozilla/net/CookieServiceParent.h"
-#include "mozilla/dom/PBrowserParent.h"
-#include "mozilla/net/NeckoParent.h"
 
 #include "mozilla/ipc/URIUtils.h"
 #include "nsCookieService.h"
 #include "nsNetUtil.h"
-#include "nsPrintfCString.h"
 
 using namespace mozilla::ipc;
-using mozilla::dom::PBrowserParent;
-using mozilla::net::NeckoParent;
 
-MOZ_WARN_UNUSED_RESULT
-static bool
-GetAppInfoFromParams(const IPC::SerializedLoadContext &aLoadContext,
-                     PBrowserParent* aBrowser,
-                     uint32_t& aAppId,
-                     bool& aIsInBrowserElement,
-                     bool& aIsPrivate) 
+static void
+GetAppInfoFromLoadContext(const IPC::SerializedLoadContext &aLoadContext,
+                          uint32_t& aAppId,
+                          bool& aIsInBrowserElement,
+                          bool& aIsPrivate)
 {
+  // TODO: bug 782542: what to do when we get null loadContext?  For now assume
+  // NECKO_NO_APP_ID.
   aAppId = NECKO_NO_APP_ID;
   aIsInBrowserElement = false;
   aIsPrivate = false;
 
-  const char* error = NeckoParent::GetValidatedAppInfo(aLoadContext, aBrowser,
-                                                       &aAppId,
-                                                       &aIsInBrowserElement);
-  if (error) {
-    NS_WARNING(nsPrintfCString("CookieServiceParent: GetAppInfoFromParams: "
-                               "FATAL error: %s: KILLING CHILD PROCESS\n",
-                               error).get());
-    return false;
+  if (aLoadContext.IsNotNull()) {
+    aAppId = aLoadContext.mAppId;
+    aIsInBrowserElement = aLoadContext.mIsInBrowserElement;
   }
 
   if (aLoadContext.IsPrivateBitValid())
     aIsPrivate = aLoadContext.mUsePrivateBrowsing;
-
-  return true;
 }
 
 namespace mozilla {
@@ -69,7 +57,6 @@ CookieServiceParent::RecvGetCookieString(const URIParams& aHost,
                                          const bool& aFromHttp,
                                          const IPC::SerializedLoadContext&
                                                aLoadContext,
-                                         PBrowserParent* aBrowser,
                                          nsCString* aResult)
 {
   if (!mCookieService)
@@ -83,15 +70,10 @@ CookieServiceParent::RecvGetCookieString(const URIParams& aHost,
 
   uint32_t appId;
   bool isInBrowserElement, isPrivate;
-  bool valid = GetAppInfoFromParams(aLoadContext, aBrowser, appId,
-                                    isInBrowserElement, isPrivate);
-  if (!valid) {
-    return false;
-  }
+  GetAppInfoFromLoadContext(aLoadContext, appId, isInBrowserElement, isPrivate);
 
   mCookieService->GetCookieStringInternal(hostURI, aIsForeign, aFromHttp, appId,
-                                          isInBrowserElement, isPrivate,
-                                          *aResult);
+                                          isInBrowserElement, isPrivate, *aResult);
   return true;
 }
 
@@ -102,8 +84,7 @@ CookieServiceParent::RecvSetCookieString(const URIParams& aHost,
                                          const nsCString& aServerTime,
                                          const bool& aFromHttp,
                                          const IPC::SerializedLoadContext&
-                                               aLoadContext,
-                                         PBrowserParent* aBrowser)
+                                               aLoadContext)
 {
   if (!mCookieService)
     return true;
@@ -116,11 +97,7 @@ CookieServiceParent::RecvSetCookieString(const URIParams& aHost,
 
   uint32_t appId;
   bool isInBrowserElement, isPrivate;
-  bool valid = GetAppInfoFromParams(aLoadContext, aBrowser, appId,
-                                    isInBrowserElement, isPrivate);
-  if (!valid) {
-    return false;
-  }
+  GetAppInfoFromLoadContext(aLoadContext, appId, isInBrowserElement, isPrivate);
 
   nsDependentCString cookieString(aCookieString, 0);
   //TODO: bug 812475, pass a real channel object
diff --git a/netwerk/cookie/CookieServiceParent.h b/netwerk/cookie/CookieServiceParent.h
index ec228ae6a67e..d51a209287ff 100644
--- a/netwerk/cookie/CookieServiceParent.h
+++ b/netwerk/cookie/CookieServiceParent.h
@@ -13,9 +13,6 @@ class nsCookieService;
 class nsIIOService;
 
 namespace mozilla {
-namespace dom {
-  class PBrowserParent;
-}
 namespace net {
 
 class CookieServiceParent : public PCookieServiceParent
@@ -30,7 +27,6 @@ protected:
                                    const bool& aFromHttp,
                                    const IPC::SerializedLoadContext&
                                          loadContext,
-                                   mozilla::dom::PBrowserParent* aBrowser,
                                    nsCString* aResult);
 
   virtual bool RecvSetCookieString(const URIParams& aHost,
@@ -39,8 +35,7 @@ protected:
                                    const nsCString& aServerTime,
                                    const bool& aFromHttp,
                                    const IPC::SerializedLoadContext&
-                                         loadContext,
-                                   mozilla::dom::PBrowserParent* aBrowser);
+                                         loadContext);
 
   nsRefPtr<nsCookieService> mCookieService;
 };
diff --git a/netwerk/cookie/PCookieService.ipdl b/netwerk/cookie/PCookieService.ipdl
index 5a004a9b1581..768eabf1f53e 100644
--- a/netwerk/cookie/PCookieService.ipdl
+++ b/netwerk/cookie/PCookieService.ipdl
@@ -6,7 +6,6 @@
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 include protocol PNecko;
-include protocol PBrowser;
 include URIParams;
 
 include "SerializedLoadContext.h";
@@ -65,8 +64,7 @@ parent:
   sync GetCookieString(URIParams host,
                        bool isForeign,
                        bool fromHttp,
-                       SerializedLoadContext loadContext,
-                       nullable PBrowser browser)
+                       SerializedLoadContext loadContext)
        returns (nsCString result);
 
   /*
@@ -103,8 +101,7 @@ parent:
                   nsCString cookieString,
                   nsCString serverTime,
                   bool fromHttp,
-                  SerializedLoadContext loadContext,
-                  nullable PBrowser browser);
+                  SerializedLoadContext loadContext);
 
   __delete__();
 };
diff --git a/netwerk/ipc/NeckoChild.cpp b/netwerk/ipc/NeckoChild.cpp
index eb415269a2d0..d47242928604 100644
--- a/netwerk/ipc/NeckoChild.cpp
+++ b/netwerk/ipc/NeckoChild.cpp
@@ -14,22 +14,17 @@
 #include "mozilla/net/FTPChannelChild.h"
 #include "mozilla/net/WebSocketChannelChild.h"
 #include "mozilla/dom/network/TCPSocketChild.h"
-#include "mozilla/Preferences.h"
 
 using mozilla::dom::TCPSocketChild;
 
 namespace mozilla {
 namespace net {
 
-static bool gDisableIPCSecurity = false;
-static const char kPrefDisableIPCSecurity[] = "network.disable.ipc.security";
-
 PNeckoChild *gNeckoChild = nullptr;
 
 // C++ file contents
 NeckoChild::NeckoChild()
 {
-  Preferences::AddBoolVarCache(&gDisableIPCSecurity, kPrefDisableIPCSecurity);
 }
 
 NeckoChild::~NeckoChild()
@@ -85,8 +80,7 @@ NeckoChild::DeallocPHttpChannel(PHttpChannelChild* channel)
 }
 
 PFTPChannelChild*
-NeckoChild::AllocPFTPChannel(PBrowserChild* aBrowser,
-                             const SerializedLoadContext& aSerialized)
+NeckoChild::AllocPFTPChannel()
 {
   // We don't allocate here: see FTPChannelChild::AsyncOpen()
   NS_RUNTIMEABORT("AllocPFTPChannel should not be called");
@@ -140,8 +134,7 @@ NeckoChild::DeallocPWyciwygChannel(PWyciwygChannelChild* channel)
 }
 
 PWebSocketChild*
-NeckoChild::AllocPWebSocket(PBrowserChild* browser,
-                            const SerializedLoadContext& aSerialized)
+NeckoChild::AllocPWebSocket(PBrowserChild* browser)
 {
   NS_NOTREACHED("AllocPWebSocket should not be called");
   return nullptr;
diff --git a/netwerk/ipc/NeckoChild.h b/netwerk/ipc/NeckoChild.h
index 9bf3021bc450..8006c4c86937 100644
--- a/netwerk/ipc/NeckoChild.h
+++ b/netwerk/ipc/NeckoChild.h
@@ -33,10 +33,9 @@ protected:
   virtual bool DeallocPCookieService(PCookieServiceChild*);
   virtual PWyciwygChannelChild* AllocPWyciwygChannel();
   virtual bool DeallocPWyciwygChannel(PWyciwygChannelChild*);
-  virtual PFTPChannelChild* AllocPFTPChannel(PBrowserChild* aBrowser,
-                                             const SerializedLoadContext& aSerialized);
+  virtual PFTPChannelChild* AllocPFTPChannel();
   virtual bool DeallocPFTPChannel(PFTPChannelChild*);
-  virtual PWebSocketChild* AllocPWebSocket(PBrowserChild*, const SerializedLoadContext&);
+  virtual PWebSocketChild* AllocPWebSocket(PBrowserChild*);
   virtual bool DeallocPWebSocket(PWebSocketChild*);
   virtual PTCPSocketChild* AllocPTCPSocket(const nsString& aHost,
                                            const uint16_t& aPort,
diff --git a/netwerk/ipc/NeckoParent.cpp b/netwerk/ipc/NeckoParent.cpp
index 7d8aceb04498..ae43859f493c 100644
--- a/netwerk/ipc/NeckoParent.cpp
+++ b/netwerk/ipc/NeckoParent.cpp
@@ -14,142 +14,30 @@
 #include "mozilla/net/WebSocketChannelParent.h"
 #include "mozilla/dom/TabParent.h"
 #include "mozilla/dom/network/TCPSocketParent.h"
-#include "mozilla/Preferences.h"
-#include "mozilla/LoadContext.h"
-#include "nsPrintfCString.h"
+
 #include "nsHTMLDNSPrefetch.h"
 
 using mozilla::dom::TabParent;
 using mozilla::net::PTCPSocketParent;
 using mozilla::dom::TCPSocketParent;
-using IPC::SerializedLoadContext;
 
 namespace mozilla {
 namespace net {
 
-static bool gDisableIPCSecurity = false;
-static const char kPrefDisableIPCSecurity[] = "network.disable.ipc.security";
-
 // C++ file contents
 NeckoParent::NeckoParent()
 {
-  Preferences::AddBoolVarCache(&gDisableIPCSecurity, kPrefDisableIPCSecurity);
 }
 
 NeckoParent::~NeckoParent()
 {
 }
 
-static PBOverrideStatus
-PBOverrideStatusFromLoadContext(const SerializedLoadContext& aSerialized)
-{
-  if (!aSerialized.IsNotNull() && aSerialized.IsPrivateBitValid()) {
-    return aSerialized.mUsePrivateBrowsing ?
-      kPBOverride_Private :
-      kPBOverride_NotPrivate;
-  }
-  return kPBOverride_Unset;
-}
-
-const char*
-NeckoParent::GetValidatedAppInfo(const SerializedLoadContext& aSerialized,
-                                 PBrowserParent* aBrowser,
-                                 uint32_t* aAppId,
-                                 bool* aInBrowserElement)
-{
-  if (!gDisableIPCSecurity) {
-    if (!aBrowser) {
-      return "missing required PBrowser argument";
-    }
-    if (!aSerialized.IsNotNull()) {
-      return "SerializedLoadContext from child is null";
-    }
-  }
-
-  *aAppId = NECKO_UNKNOWN_APP_ID;
-  *aInBrowserElement = false;
-
-  if (aBrowser) {
-    nsRefPtr<TabParent> tabParent = static_cast<TabParent*>(aBrowser);
-
-    *aAppId = tabParent->OwnOrContainingAppId();
-    *aInBrowserElement = tabParent->IsBrowserElement();
-
-    if (*aAppId == NECKO_UNKNOWN_APP_ID) {
-      return "TabParent reports appId=NECKO_UNKNOWN_APP_ID!";
-    }
-    // We may get appID=NO_APP if child frame is neither a browser nor an app
-    if (*aAppId == NECKO_NO_APP_ID) {
-      if (tabParent->HasOwnApp()) {
-        return "TabParent reports NECKO_NO_APP_ID but also is an app";
-      }
-      if (!gDisableIPCSecurity && tabParent->IsBrowserElement()) {
-        // <iframe mozbrowser> which doesn't have an <iframe mozapp> above it.
-        // This is not supported now, and we'll need to do a code audit to make
-        // sure we can handle it (i.e don't short-circuit using separate
-        // namespace if just appID==0)
-        return "TabParent reports appId=NECKO_NO_APP_ID but is a mozbrowser";
-      }
-    }
-  } else {
-    // Only trust appId/inBrowser from child-side loadcontext if we're in
-    // testing mode: allows xpcshell tests to masquerade as apps
-    MOZ_ASSERT(gDisableIPCSecurity);
-    if (!gDisableIPCSecurity) {
-      return "internal error";
-    }
-    if (aSerialized.IsNotNull()) {
-      *aAppId = aSerialized.mAppId;
-      *aInBrowserElement = aSerialized.mIsInBrowserElement;
-    } else {
-      *aAppId = NECKO_NO_APP_ID;
-    }
-  }
-  return nullptr;
-}
-
-const char *
-NeckoParent::CreateChannelLoadContext(PBrowserParent* aBrowser,
-                                      const SerializedLoadContext& aSerialized,
-                                      nsCOMPtr<nsILoadContext> &aResult)
-{
-  uint32_t appId = NECKO_UNKNOWN_APP_ID;
-  bool inBrowser = false;
-  nsIDOMElement* topFrameElement = nullptr;
-  const char* error = GetValidatedAppInfo(aSerialized, aBrowser, &appId, &inBrowser);
-  if (error) {
-    return error;
-  }
-
-  if (aBrowser) {
-    nsRefPtr<TabParent> tabParent = static_cast<TabParent*>(aBrowser);
-    topFrameElement = tabParent->GetOwnerElement();
-  }
-
-  // if gDisableIPCSecurity, we may not have a LoadContext to set. This is
-  // the common case for most xpcshell tests.
-  if (aSerialized.IsNotNull()) {
-    aResult = new LoadContext(aSerialized, topFrameElement, appId, inBrowser);
-  }
-
-  return nullptr;
-}
-
 PHttpChannelParent*
-NeckoParent::AllocPHttpChannel(PBrowserParent* aBrowser,
-                               const SerializedLoadContext& aSerialized)
+NeckoParent::AllocPHttpChannel(PBrowserParent* browser,
+                               const SerializedLoadContext& loadContext)
 {
-  nsCOMPtr<nsILoadContext> loadContext;
-  const char *error = CreateChannelLoadContext(aBrowser, aSerialized,
-                                               loadContext);
-  if (error) {
-    NS_WARNING(nsPrintfCString("NeckoParent::AllocPHttpChannel: "
-                               "FATAL error: %s: KILLING CHILD PROCESS\n",
-                               error).get());
-    return nullptr;
-  }
-  PBOverrideStatus overrideStatus = PBOverrideStatusFromLoadContext(aSerialized);
-  HttpChannelParent *p = new HttpChannelParent(aBrowser, loadContext, overrideStatus);
+  HttpChannelParent *p = new HttpChannelParent(browser, loadContext);
   p->AddRef();
   return p;
 }
@@ -163,20 +51,9 @@ NeckoParent::DeallocPHttpChannel(PHttpChannelParent* channel)
 }
 
 PFTPChannelParent*
-NeckoParent::AllocPFTPChannel(PBrowserParent* aBrowser,
-                              const SerializedLoadContext& aSerialized)
+NeckoParent::AllocPFTPChannel()
 {
-  nsCOMPtr<nsILoadContext> loadContext;
-  const char *error = CreateChannelLoadContext(aBrowser, aSerialized,
-                                               loadContext);
-  if (error) {
-    NS_WARNING(nsPrintfCString("NeckoParent::AllocPFTPChannel: "
-                               "FATAL error: %s: KILLING CHILD PROCESS\n",
-                               error).get());
-    return nullptr;
-  }
-  PBOverrideStatus overrideStatus = PBOverrideStatusFromLoadContext(aSerialized);
-  FTPChannelParent *p = new FTPChannelParent(loadContext, overrideStatus);
+  FTPChannelParent *p = new FTPChannelParent();
   p->AddRef();
   return p;
 }
@@ -219,23 +96,10 @@ NeckoParent::DeallocPWyciwygChannel(PWyciwygChannelParent* channel)
 }
 
 PWebSocketParent*
-NeckoParent::AllocPWebSocket(PBrowserParent* browser,
-                             const SerializedLoadContext& serialized)
+NeckoParent::AllocPWebSocket(PBrowserParent* browser)
 {
-  nsCOMPtr<nsILoadContext> loadContext;
-  const char *error = CreateChannelLoadContext(browser, serialized,
-                                               loadContext);
-  if (error) {
-    NS_WARNING(nsPrintfCString("NeckoParent::AllocPWebSocket: "
-                               "FATAL error: %s: KILLING CHILD PROCESS\n",
-                               error).get());
-    return nullptr;
-  }
-
   TabParent* tabParent = static_cast<TabParent*>(browser);
-  PBOverrideStatus overrideStatus = PBOverrideStatusFromLoadContext(serialized);
-  WebSocketChannelParent* p = new WebSocketChannelParent(tabParent, loadContext,
-                                                         overrideStatus);
+  WebSocketChannelParent* p = new WebSocketChannelParent(tabParent);
   p->AddRef();
   return p;
 }
diff --git a/netwerk/ipc/NeckoParent.h b/netwerk/ipc/NeckoParent.h
index a14d1cd7c4ba..1112e1046a10 100644
--- a/netwerk/ipc/NeckoParent.h
+++ b/netwerk/ipc/NeckoParent.h
@@ -14,13 +14,6 @@
 namespace mozilla {
 namespace net {
 
-// Used to override channel Private Browsing status if needed.
-enum PBOverrideStatus {
-  kPBOverride_Unset = 0,
-  kPBOverride_Private,
-  kPBOverride_NotPrivate
-};
-
 // Header file contents
 class NeckoParent :
   public PNeckoParent
@@ -29,27 +22,6 @@ public:
   NeckoParent();
   virtual ~NeckoParent();
 
-  MOZ_WARN_UNUSED_RESULT
-  static const char *
-  GetValidatedAppInfo(const SerializedLoadContext& aSerialized,
-                      PBrowserParent* aBrowser,
-                      uint32_t* aAppId,
-                      bool* aInBrowserElement);
-
-  /*
-   * Creates LoadContext for parent-side of an e10s channel.
-   *
-   * Values from PBrowserParent are more secure, and override those set in
-   * SerializedLoadContext.
-   *
-   * Returns null if successful, or an error string if failed.
-   */
-  MOZ_WARN_UNUSED_RESULT
-  static const char*
-  CreateChannelLoadContext(PBrowserParent* aBrowser,
-                           const SerializedLoadContext& aSerialized,
-                           nsCOMPtr<nsILoadContext> &aResult);
-
 protected:
   virtual PHttpChannelParent* AllocPHttpChannel(PBrowserParent*,
                                                 const SerializedLoadContext&);
@@ -58,11 +30,9 @@ protected:
   virtual bool DeallocPCookieService(PCookieServiceParent*);
   virtual PWyciwygChannelParent* AllocPWyciwygChannel();
   virtual bool DeallocPWyciwygChannel(PWyciwygChannelParent*);
-  virtual PFTPChannelParent* AllocPFTPChannel(PBrowserParent* aBrowser,
-                                              const SerializedLoadContext& aSerialized);
+  virtual PFTPChannelParent* AllocPFTPChannel();
   virtual bool DeallocPFTPChannel(PFTPChannelParent*);
-  virtual PWebSocketParent* AllocPWebSocket(PBrowserParent* browser,
-                                            const SerializedLoadContext& aSerialized);
+  virtual PWebSocketParent* AllocPWebSocket(PBrowserParent* browser);
   virtual bool DeallocPWebSocket(PWebSocketParent*);
   virtual PTCPSocketParent* AllocPTCPSocket(const nsString& aHost,
                                             const uint16_t& aPort,
@@ -81,6 +51,7 @@ protected:
   virtual bool RecvCancelHTMLDNSPrefetch(const nsString& hostname,
                                          const uint16_t& flags,
                                          const nsresult& reason);
+
 };
 
 } // namespace net
diff --git a/netwerk/ipc/PNecko.ipdl b/netwerk/ipc/PNecko.ipdl
index 18211afa99c4..9330fb01fe3b 100644
--- a/netwerk/ipc/PNecko.ipdl
+++ b/netwerk/ipc/PNecko.ipdl
@@ -40,8 +40,8 @@ parent:
   PHttpChannel(nullable PBrowser browser,
                SerializedLoadContext loadContext);
   PWyciwygChannel();
-  PFTPChannel(PBrowser browser, SerializedLoadContext loadContext);
-  PWebSocket(PBrowser browser, SerializedLoadContext loadContext);
+  PFTPChannel();
+  PWebSocket(PBrowser browser);
   PTCPSocket(nsString host, uint16_t port, bool useSSL, nsString binaryType,
              nullable PBrowser browser);
 
diff --git a/netwerk/protocol/ftp/FTPChannelChild.cpp b/netwerk/protocol/ftp/FTPChannelChild.cpp
index 9f10b9af82ee..bb799fbdcd96 100644
--- a/netwerk/protocol/ftp/FTPChannelChild.cpp
+++ b/netwerk/protocol/ftp/FTPChannelChild.cpp
@@ -7,9 +7,8 @@
 
 #include "mozilla/net/NeckoChild.h"
 #include "mozilla/net/FTPChannelChild.h"
-#include "mozilla/dom/TabChild.h"
 #include "nsFtpProtocolHandler.h"
-#include "nsITabChild.h"
+
 #include "nsStringStream.h"
 #include "nsMimeTypes.h"
 #include "nsNetUtil.h"
@@ -156,18 +155,8 @@ FTPChannelChild::AsyncOpen(::nsIStreamListener* listener, nsISupports* aContext)
   if (NS_FAILED(rv))
     return rv;
 
-  mozilla::dom::TabChild* tabChild = nullptr;
-  nsCOMPtr<nsITabChild> iTabChild;
-  NS_QueryNotificationCallbacks(mCallbacks, mLoadGroup,
-                                NS_GET_IID(nsITabChild),
-                                getter_AddRefs(iTabChild));
-  GetCallback(iTabChild);
-  if (iTabChild) {
-    tabChild = static_cast<mozilla::dom::TabChild*>(iTabChild.get());
-  }
-
   // FIXME: like bug 558623, merge constructor+SendAsyncOpen into 1 IPC msg
-  gNeckoChild->SendPFTPChannelConstructor(this, tabChild, IPC::SerializedLoadContext(this));
+  gNeckoChild->SendPFTPChannelConstructor(this);
   mListener = listener;
   mListenerContext = aContext;
 
@@ -181,7 +170,8 @@ FTPChannelChild::AsyncOpen(::nsIStreamListener* listener, nsISupports* aContext)
   OptionalInputStreamParams uploadStream;
   SerializeInputStream(mUploadStream, uploadStream);
 
-  SendAsyncOpen(uri, mStartPos, mEntityID, uploadStream);
+  SendAsyncOpen(uri, mStartPos, mEntityID, uploadStream,
+                IPC::SerializedLoadContext(this));
 
   // The socket transport layer in the chrome process now has a logical ref to
   // us until OnStopRequest is called.
@@ -519,22 +509,11 @@ FTPChannelChild::Resume()
 NS_IMETHODIMP
 FTPChannelChild::ConnectParent(uint32_t id)
 {
-  mozilla::dom::TabChild* tabChild = nullptr;
-  nsCOMPtr<nsITabChild> iTabChild;
-  NS_QueryNotificationCallbacks(mCallbacks, mLoadGroup,
-                                NS_GET_IID(nsITabChild),
-                                getter_AddRefs(iTabChild));
-  GetCallback(iTabChild);
-  if (iTabChild) {
-    tabChild = static_cast<mozilla::dom::TabChild*>(iTabChild.get());
-  }
-
   // The socket transport in the chrome process now holds a logical ref to us
   // until OnStopRequest, or we do a redirect, or we hit an IPDL error.
   AddIPDLReference();
 
-  if (!gNeckoChild->SendPFTPChannelConstructor(this, tabChild,
-                                               IPC::SerializedLoadContext(this)))
+  if (!gNeckoChild->SendPFTPChannelConstructor(this))
     return NS_ERROR_FAILURE;
 
   if (!SendConnectChannel(id))
diff --git a/netwerk/protocol/ftp/FTPChannelParent.cpp b/netwerk/protocol/ftp/FTPChannelParent.cpp
index c69e25e03c43..44cb7bb20a35 100644
--- a/netwerk/protocol/ftp/FTPChannelParent.cpp
+++ b/netwerk/protocol/ftp/FTPChannelParent.cpp
@@ -23,10 +23,8 @@ using namespace mozilla::ipc;
 namespace mozilla {
 namespace net {
 
-FTPChannelParent::FTPChannelParent(nsILoadContext* aLoadContext, PBOverrideStatus aOverrideStatus)
+FTPChannelParent::FTPChannelParent()
   : mIPCClosed(false)
-  , mLoadContext(aLoadContext)
-  , mPBOverride(aOverrideStatus)
 {
   nsIProtocolHandler* handler;
   CallGetService(NS_NETWORK_PROTOCOL_CONTRACTID_PREFIX "ftp", &handler);
@@ -64,7 +62,8 @@ bool
 FTPChannelParent::RecvAsyncOpen(const URIParams& aURI,
                                 const uint64_t& aStartPos,
                                 const nsCString& aEntityID,
-                                const OptionalInputStreamParams& aUploadStream)
+                                const OptionalInputStreamParams& aUploadStream,
+                                const IPC::SerializedLoadContext& loadContext)
 {
   nsCOMPtr<nsIURI> uri = DeserializeURI(aURI);
   if (!uri)
@@ -88,11 +87,7 @@ FTPChannelParent::RecvAsyncOpen(const URIParams& aURI,
     return SendFailedAsyncOpen(rv);
 
   mChannel = static_cast<nsFtpChannel*>(chan.get());
-
-  if (mPBOverride != kPBOverride_Unset) {
-    mChannel->SetPrivate(mPBOverride == kPBOverride_Private ? true : false);
-  }
-
+  
   nsCOMPtr<nsIInputStream> upload = DeserializeInputStream(aUploadStream);
   if (upload) {
     // contentType and contentLength are ignored
@@ -105,6 +100,14 @@ FTPChannelParent::RecvAsyncOpen(const URIParams& aURI,
   if (NS_FAILED(rv))
     return SendFailedAsyncOpen(rv);
 
+  if (loadContext.IsNotNull())
+    mLoadContext = new LoadContext(loadContext);
+  else if (loadContext.IsPrivateBitValid()) {
+    nsCOMPtr<nsIPrivateBrowsingChannel> pbChannel = do_QueryInterface(chan);
+    if (pbChannel)
+      pbChannel->SetPrivate(loadContext.mUsePrivateBrowsing);
+  }
+
   rv = mChannel->AsyncOpen(this, nullptr);
   if (NS_FAILED(rv))
     return SendFailedAsyncOpen(rv);
diff --git a/netwerk/protocol/ftp/FTPChannelParent.h b/netwerk/protocol/ftp/FTPChannelParent.h
index ab048833aee4..39e5fff7df01 100644
--- a/netwerk/protocol/ftp/FTPChannelParent.h
+++ b/netwerk/protocol/ftp/FTPChannelParent.h
@@ -10,7 +10,6 @@
 
 #include "mozilla/net/PFTPChannelParent.h"
 #include "mozilla/net/NeckoCommon.h"
-#include "mozilla/net/NeckoParent.h"
 #include "nsIParentChannel.h"
 #include "nsIInterfaceRequestor.h"
 #include "nsILoadContext.h"
@@ -31,14 +30,15 @@ public:
   NS_DECL_NSIPARENTCHANNEL
   NS_DECL_NSIINTERFACEREQUESTOR
 
-  FTPChannelParent(nsILoadContext* aLoadContext, PBOverrideStatus aOverrideStatus);
+  FTPChannelParent();
   virtual ~FTPChannelParent();
 
 protected:
   virtual bool RecvAsyncOpen(const URIParams& uri,
                              const uint64_t& startPos,
                              const nsCString& entityID,
-                             const OptionalInputStreamParams& uploadStream) MOZ_OVERRIDE;
+                             const OptionalInputStreamParams& uploadStream,
+                             const IPC::SerializedLoadContext& loadContext) MOZ_OVERRIDE;
   virtual bool RecvConnectChannel(const uint32_t& channelId) MOZ_OVERRIDE;
   virtual bool RecvCancel(const nsresult& status) MOZ_OVERRIDE;
   virtual bool RecvSuspend() MOZ_OVERRIDE;
@@ -51,8 +51,6 @@ protected:
   bool mIPCClosed;
 
   nsCOMPtr<nsILoadContext> mLoadContext;
-
-  PBOverrideStatus mPBOverride;
 };
 
 } // namespace net
diff --git a/netwerk/protocol/ftp/PFTPChannel.ipdl b/netwerk/protocol/ftp/PFTPChannel.ipdl
index e74a5fb24181..7c2929ec630c 100644
--- a/netwerk/protocol/ftp/PFTPChannel.ipdl
+++ b/netwerk/protocol/ftp/PFTPChannel.ipdl
@@ -13,6 +13,7 @@ include protocol PBlob; //FIXME: bug #792908
 
 include "SerializedLoadContext.h";
 
+using IPC::SerializedLoadContext;
 using PRTime;
 
 namespace mozilla {
@@ -28,7 +29,8 @@ parent:
   AsyncOpen(URIParams uri,
             uint64_t startPos,
             nsCString entityID,
-            OptionalInputStreamParams uploadStream);
+            OptionalInputStreamParams uploadStream,
+            SerializedLoadContext loadContext);
 
   ConnectChannel(uint32_t channelId);
   Cancel(nsresult status);
diff --git a/netwerk/protocol/http/HttpChannelParent.cpp b/netwerk/protocol/http/HttpChannelParent.cpp
index 89699a45ab64..74a17cb89a11 100644
--- a/netwerk/protocol/http/HttpChannelParent.cpp
+++ b/netwerk/protocol/http/HttpChannelParent.cpp
@@ -34,8 +34,7 @@ namespace mozilla {
 namespace net {
 
 HttpChannelParent::HttpChannelParent(PBrowserParent* iframeEmbedding,
-                                     nsILoadContext* aLoadContext,
-                                     PBOverrideStatus aOverrideStatus)
+                                     const IPC::SerializedLoadContext& loadContext)
   : mIPCClosed(false)
   , mStoredStatus(NS_OK)
   , mStoredProgress(0)
@@ -43,8 +42,7 @@ HttpChannelParent::HttpChannelParent(PBrowserParent* iframeEmbedding,
   , mSentRedirect1Begin(false)
   , mSentRedirect1BeginFailed(false)
   , mReceivedRedirect2Verify(false)
-  , mPBOverride(aOverrideStatus)
-  , mLoadContext(aLoadContext)
+  , mPBOverride(kPBOverride_Unset)
 {
   // Ensure gHttpHandler is initialized: we need the atom table up and running.
   nsIHttpProtocolHandler* handler;
@@ -52,6 +50,18 @@ HttpChannelParent::HttpChannelParent(PBrowserParent* iframeEmbedding,
   NS_ASSERTION(handler, "no http handler");
 
   mTabParent = static_cast<mozilla::dom::TabParent*>(iframeEmbedding);
+
+  if (loadContext.IsNotNull()) {
+    if (mTabParent) {
+      mLoadContext = new LoadContext(loadContext, mTabParent->GetOwnerElement());
+    } else {
+      mLoadContext = new LoadContext(loadContext);
+    }
+  } else if (loadContext.IsPrivateBitValid()) {
+    // Don't have channel yet: override PB status after we create it.
+    mPBOverride = loadContext.mUsePrivateBrowsing ? kPBOverride_Private
+                                                  : kPBOverride_NotPrivate;
+  }
 }
 
 HttpChannelParent::~HttpChannelParent()
diff --git a/netwerk/protocol/http/HttpChannelParent.h b/netwerk/protocol/http/HttpChannelParent.h
index 6796ef58e085..fc7a9b7af2cc 100644
--- a/netwerk/protocol/http/HttpChannelParent.h
+++ b/netwerk/protocol/http/HttpChannelParent.h
@@ -12,7 +12,6 @@
 #include "mozilla/dom/PBrowserParent.h"
 #include "mozilla/net/PHttpChannelParent.h"
 #include "mozilla/net/NeckoCommon.h"
-#include "mozilla/net/NeckoParent.h"
 #include "nsIParentRedirectingChannel.h"
 #include "nsIProgressEventSink.h"
 #include "nsHttpChannel.h"
@@ -45,8 +44,7 @@ public:
   NS_DECL_NSIINTERFACEREQUESTOR
 
   HttpChannelParent(mozilla::dom::PBrowserParent* iframeEmbedding,
-                    nsILoadContext* aLoadContext,
-                    PBOverrideStatus aStatus);
+                    const IPC::SerializedLoadContext& loadContext);
   virtual ~HttpChannelParent();
 
 protected:
@@ -110,6 +108,12 @@ private:
   bool mSentRedirect1BeginFailed    : 1;
   bool mReceivedRedirect2Verify     : 1;
 
+  // Used to override channel Private Browsing status if needed.
+  enum PBOverrideStatus {
+    kPBOverride_Unset = 0,
+    kPBOverride_Private,
+    kPBOverride_NotPrivate
+  };
   PBOverrideStatus mPBOverride;
 
   nsCOMPtr<nsILoadContext> mLoadContext;
diff --git a/netwerk/protocol/websocket/PWebSocket.ipdl b/netwerk/protocol/websocket/PWebSocket.ipdl
index 9c111eab4592..1f9301f4a2a7 100644
--- a/netwerk/protocol/websocket/PWebSocket.ipdl
+++ b/netwerk/protocol/websocket/PWebSocket.ipdl
@@ -27,7 +27,8 @@ parent:
   AsyncOpen(URIParams aURI,
             nsCString aOrigin,
             nsCString aProtocol,
-            bool aSecure);
+            bool aSecure,
+            SerializedLoadContext loadContext);
   Close(uint16_t code, nsCString reason);
   SendMsg(nsCString aMsg);
   SendBinaryMsg(nsCString aMsg);
diff --git a/netwerk/protocol/websocket/WebSocketChannelChild.cpp b/netwerk/protocol/websocket/WebSocketChannelChild.cpp
index b4c395964476..6e4baa678d26 100644
--- a/netwerk/protocol/websocket/WebSocketChannelChild.cpp
+++ b/netwerk/protocol/websocket/WebSocketChannelChild.cpp
@@ -338,9 +338,9 @@ WebSocketChannelChild::AsyncOpen(nsIURI *aURI,
   // Corresponding release in DeallocPWebSocket
   AddIPDLReference();
 
-  gNeckoChild->SendPWebSocketConstructor(this, tabChild,
-                                         IPC::SerializedLoadContext(this));
-  if (!SendAsyncOpen(uri, nsCString(aOrigin), mProtocol, mEncrypted))
+  gNeckoChild->SendPWebSocketConstructor(this, tabChild);
+  if (!SendAsyncOpen(uri, nsCString(aOrigin), mProtocol, mEncrypted,
+                     IPC::SerializedLoadContext(this)))
     return NS_ERROR_UNEXPECTED;
 
   mOriginalURI = aURI;
diff --git a/netwerk/protocol/websocket/WebSocketChannelParent.cpp b/netwerk/protocol/websocket/WebSocketChannelParent.cpp
index 2edabddce278..8a659c7e5c3d 100644
--- a/netwerk/protocol/websocket/WebSocketChannelParent.cpp
+++ b/netwerk/protocol/websocket/WebSocketChannelParent.cpp
@@ -7,6 +7,7 @@
 #include "WebSocketLog.h"
 #include "WebSocketChannelParent.h"
 #include "nsIAuthPromptProvider.h"
+#include "mozilla/LoadContext.h"
 #include "mozilla/ipc/InputStreamUtils.h"
 #include "mozilla/ipc/URIUtils.h"
 
@@ -19,15 +20,10 @@ NS_IMPL_THREADSAFE_ISUPPORTS2(WebSocketChannelParent,
                               nsIWebSocketListener,
                               nsIInterfaceRequestor)
 
-WebSocketChannelParent::WebSocketChannelParent(nsIAuthPromptProvider* aAuthProvider,
-                                               nsILoadContext* aLoadContext,
-                                               PBOverrideStatus aOverrideStatus)
+WebSocketChannelParent::WebSocketChannelParent(nsIAuthPromptProvider* aAuthProvider)
   : mAuthProvider(aAuthProvider)
-  , mLoadContext(aLoadContext)
   , mIPCOpen(true)
 {
-  // Websocket channels can't have a private browsing override
-  MOZ_ASSERT_IF(!aLoadContext, aOverrideStatus == kPBOverride_Unset);
 #if defined(PR_LOGGING)
   if (!webSocketLog)
     webSocketLog = PR_NewLogModule("nsWebSocket");
@@ -51,7 +47,8 @@ bool
 WebSocketChannelParent::RecvAsyncOpen(const URIParams& aURI,
                                       const nsCString& aOrigin,
                                       const nsCString& aProtocol,
-                                      const bool& aSecure)
+                                      const bool& aSecure,
+                                      const IPC::SerializedLoadContext& loadContext)
 {
   LOG(("WebSocketChannelParent::RecvAsyncOpen() %p\n", this));
 
@@ -68,6 +65,14 @@ WebSocketChannelParent::RecvAsyncOpen(const URIParams& aURI,
   if (NS_FAILED(rv))
     goto fail;
 
+  if (loadContext.IsNotNull())
+    mLoadContext = new LoadContext(loadContext);
+#ifdef DEBUG
+  else
+    // websocket channels cannot have a private bit override
+    MOZ_ASSERT(!loadContext.IsPrivateBitValid());
+#endif
+
   rv = mChannel->SetNotificationCallbacks(this);
   if (NS_FAILED(rv))
     goto fail;
diff --git a/netwerk/protocol/websocket/WebSocketChannelParent.h b/netwerk/protocol/websocket/WebSocketChannelParent.h
index 760b2975dd76..fa70ad72a355 100644
--- a/netwerk/protocol/websocket/WebSocketChannelParent.h
+++ b/netwerk/protocol/websocket/WebSocketChannelParent.h
@@ -8,7 +8,6 @@
 #define mozilla_net_WebSocketChannelParent_h
 
 #include "mozilla/net/PWebSocketParent.h"
-#include "mozilla/net/NeckoParent.h"
 #include "nsIInterfaceRequestor.h"
 #include "nsIWebSocketListener.h"
 #include "nsIWebSocketChannel.h"
@@ -30,15 +29,14 @@ class WebSocketChannelParent : public PWebSocketParent,
   NS_DECL_NSIWEBSOCKETLISTENER
   NS_DECL_NSIINTERFACEREQUESTOR
 
-  WebSocketChannelParent(nsIAuthPromptProvider* aAuthProvider,
-                         nsILoadContext* aLoadContext,
-                         PBOverrideStatus aOverrideStatus);
+  WebSocketChannelParent(nsIAuthPromptProvider* aAuthProvider);
 
  private:
   bool RecvAsyncOpen(const URIParams& aURI,
                      const nsCString& aOrigin,
                      const nsCString& aProtocol,
-                     const bool& aSecure);
+                     const bool& aSecure,
+                     const IPC::SerializedLoadContext& loadContext);
   bool RecvClose(const uint16_t & code, const nsCString & reason);
   bool RecvSendMsg(const nsCString& aMsg);
   bool RecvSendBinaryMsg(const nsCString& aMsg);
diff --git a/netwerk/protocol/wyciwyg/PWyciwygChannel.ipdl b/netwerk/protocol/wyciwyg/PWyciwygChannel.ipdl
index 23211f657d0f..9e0bb345debf 100644
--- a/netwerk/protocol/wyciwyg/PWyciwygChannel.ipdl
+++ b/netwerk/protocol/wyciwyg/PWyciwygChannel.ipdl
@@ -3,7 +3,6 @@
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 include protocol PNecko;
-include protocol PBrowser;
 include URIParams;
 
 include "SerializedLoadContext.h";
@@ -24,8 +23,7 @@ parent:
   Init(URIParams uri);
   AsyncOpen(URIParams             originalURI,
             uint32_t              loadFlags,
-            SerializedLoadContext loadContext,
-            PBrowser browser);
+            SerializedLoadContext loadContext);
 
   // methods corresponding to those of nsIWyciwygChannel
   WriteToCacheEntry(nsString data);
diff --git a/netwerk/protocol/wyciwyg/WyciwygChannelChild.cpp b/netwerk/protocol/wyciwyg/WyciwygChannelChild.cpp
index 2b247bf92abd..63e102ce3f42 100644
--- a/netwerk/protocol/wyciwyg/WyciwygChannelChild.cpp
+++ b/netwerk/protocol/wyciwyg/WyciwygChannelChild.cpp
@@ -6,7 +6,6 @@
 
 #include "mozilla/net/NeckoChild.h"
 #include "WyciwygChannelChild.h"
-#include "mozilla/dom/TabChild.h"
 
 #include "nsCharsetSource.h"
 #include "nsStringStream.h"
@@ -593,16 +592,7 @@ WyciwygChannelChild::AsyncOpen(nsIStreamListener *aListener, nsISupports *aConte
   URIParams originalURI;
   SerializeURI(mOriginalURI, originalURI);
 
-  mozilla::dom::TabChild* tabChild = nullptr;
-  nsCOMPtr<nsITabChild> iTabChild;
-  NS_QueryNotificationCallbacks(mCallbacks, mLoadGroup,
-                                NS_GET_IID(nsITabChild),
-                                getter_AddRefs(iTabChild));
-  if (iTabChild) {
-    tabChild = static_cast<mozilla::dom::TabChild*>(iTabChild.get());
-  }
-
-  SendAsyncOpen(originalURI, mLoadFlags, IPC::SerializedLoadContext(this), tabChild);
+  SendAsyncOpen(originalURI, mLoadFlags, IPC::SerializedLoadContext(this));
 
   mState = WCC_OPENED;
 
diff --git a/netwerk/protocol/wyciwyg/WyciwygChannelParent.cpp b/netwerk/protocol/wyciwyg/WyciwygChannelParent.cpp
index d6711cdde46c..9900c26f78f5 100644
--- a/netwerk/protocol/wyciwyg/WyciwygChannelParent.cpp
+++ b/netwerk/protocol/wyciwyg/WyciwygChannelParent.cpp
@@ -11,8 +11,8 @@
 #include "nsCharsetSource.h"
 #include "nsISerializable.h"
 #include "nsSerializationHelper.h"
+#include "mozilla/LoadContext.h"
 #include "mozilla/ipc/URIUtils.h"
-#include "mozilla/net/NeckoParent.h"
 
 using namespace mozilla::ipc;
 
@@ -86,8 +86,7 @@ WyciwygChannelParent::RecvInit(const URIParams& aURI)
 bool
 WyciwygChannelParent::RecvAsyncOpen(const URIParams& aOriginal,
                                     const uint32_t& aLoadFlags,
-                                    const IPC::SerializedLoadContext& loadContext,
-                                    PBrowserParent* aParent)
+                                    const IPC::SerializedLoadContext& loadContext)
 {
   nsCOMPtr<nsIURI> original = DeserializeURI(aOriginal);
   if (!original)
@@ -108,15 +107,9 @@ WyciwygChannelParent::RecvAsyncOpen(const URIParams& aOriginal,
   if (NS_FAILED(rv))
     return SendCancelEarly(rv);
 
-  const char* error = NeckoParent::CreateChannelLoadContext(aParent, loadContext,
-                                                            mLoadContext);
-  if (error) {
-    NS_WARNING(nsPrintfCString("WyciwygChannelParent::RecvAsyncOpen: error: %s\n",
-                               error).get());
-    return false;
-  }
-
-  if (!mLoadContext && loadContext.IsPrivateBitValid()) {
+  if (loadContext.IsNotNull())
+    mLoadContext = new LoadContext(loadContext);
+  else if (loadContext.IsPrivateBitValid()) {
     nsCOMPtr<nsIPrivateBrowsingChannel> pbChannel = do_QueryInterface(mChannel);
     if (pbChannel)
       pbChannel->SetPrivate(loadContext.mUsePrivateBrowsing);
diff --git a/netwerk/protocol/wyciwyg/WyciwygChannelParent.h b/netwerk/protocol/wyciwyg/WyciwygChannelParent.h
index 628b8df30a3a..819c31031f87 100644
--- a/netwerk/protocol/wyciwyg/WyciwygChannelParent.h
+++ b/netwerk/protocol/wyciwyg/WyciwygChannelParent.h
@@ -14,10 +14,6 @@
 #include "nsILoadContext.h"
 
 namespace mozilla {
-namespace dom {
-  class PBrowserParent;
-}
-
 namespace net {
 
 class WyciwygChannelParent : public PWyciwygChannelParent
@@ -37,8 +33,7 @@ protected:
   virtual bool RecvInit(const URIParams& uri);
   virtual bool RecvAsyncOpen(const URIParams& original,
                              const uint32_t& loadFlags,
-                             const IPC::SerializedLoadContext& loadContext,
-                             PBrowserParent* parent);
+                             const IPC::SerializedLoadContext& loadContext);
   virtual bool RecvWriteToCacheEntry(const nsString& data);
   virtual bool RecvCloseCacheEntry(const nsresult& reason);
   virtual bool RecvSetCharsetAndSource(const int32_t& source,
diff --git a/testing/xpcshell/head.js b/testing/xpcshell/head.js
index 016e3dd6cf66..c7885111e920 100644
--- a/testing/xpcshell/head.js
+++ b/testing/xpcshell/head.js
@@ -36,27 +36,16 @@ let (ios = Components.classes["@mozilla.org/network/io-service;1"]
   ios.offline = false;
 }
 
-// Determine if we're running on parent or child
-let runningInParent = true;
+// Disable IPv6 lookups for 'localhost' on windows.
 try {
-  runningInParent = Components.classes["@mozilla.org/xre/runtime;1"].
-                    getService(Components.interfaces.nsIXULRuntime).processType
-                    == Components.interfaces.nsIXULRuntime.PROCESS_TYPE_DEFAULT;
-} 
-catch (e) { }
-
-try {
-  if (runningInParent) {
-    let prefs = Components.classes["@mozilla.org/preferences-service;1"]
-                .getService(Components.interfaces.nsIPrefBranch);
-
-    // disable necko IPC security checks for xpcshell, as they lack the
-    // docshells needed to pass them
-    prefs.setBoolPref("network.disable.ipc.security", true);
-
-    // Disable IPv6 lookups for 'localhost' on windows.
-    if ("@mozilla.org/windows-registry-key;1" in Components.classes) {
-      prefs.setCharPref("network.dns.ipv4OnlyDomains", "localhost");
+  if ("@mozilla.org/windows-registry-key;1" in Components.classes) {
+    let processType = Components.classes["@mozilla.org/xre/runtime;1"].
+      getService(Components.interfaces.nsIXULRuntime).processType;
+    if (processType == Components.interfaces.nsIXULRuntime.PROCESS_TYPE_DEFAULT) {
+      let (prefs = Components.classes["@mozilla.org/preferences-service;1"]
+                   .getService(Components.interfaces.nsIPrefBranch)) {
+        prefs.setCharPref("network.dns.ipv4OnlyDomains", "localhost");
+      }
     }
   }
 }
@@ -68,7 +57,9 @@ catch (e) { }
 // Note that if we're in a child process, we don't want to init the
 // crashreporter component.
 try { // nsIXULRuntime is not available in some configurations.
-  if (runningInParent &&
+  let processType = Components.classes["@mozilla.org/xre/runtime;1"].
+    getService(Components.interfaces.nsIXULRuntime).processType;
+  if (processType == Components.interfaces.nsIXULRuntime.PROCESS_TYPE_DEFAULT &&
       "@mozilla.org/toolkit/crash-reporter;1" in Components.classes) {
     // Remember to update </toolkit/crashreporter/test/unit/test_crashreporter.js>
     // too if you change this initial setting.
@@ -809,7 +800,11 @@ function do_get_profile() {
 function do_load_child_test_harness()
 {
   // Make sure this isn't called from child process
-  if (!runningInParent) {
+  var runtime = Components.classes["@mozilla.org/xre/app-info;1"]
+                  .getService(Components.interfaces.nsIXULRuntime);
+  if (runtime.processType != 
+            Components.interfaces.nsIXULRuntime.PROCESS_TYPE_DEFAULT) 
+  {
     do_throw("run_test_in_child cannot be called from child!");
   }
 
diff --git a/uriloader/prefetch/OfflineCacheUpdateChild.cpp b/uriloader/prefetch/OfflineCacheUpdateChild.cpp
index 203d11e0f415..96e3e72a70af 100644
--- a/uriloader/prefetch/OfflineCacheUpdateChild.cpp
+++ b/uriloader/prefetch/OfflineCacheUpdateChild.cpp
@@ -441,6 +441,7 @@ OfflineCacheUpdateChild::Schedule()
     // a reference to us. Will be released in RecvFinish() that identifies 
     // the work has been done.
     child->SendPOfflineCacheUpdateConstructor(this, manifestURI, documentURI,
+                                              mInBrowser, mAppID,
                                               stickDocument);
 
     mIPCActivated = true;
diff --git a/uriloader/prefetch/OfflineCacheUpdateParent.cpp b/uriloader/prefetch/OfflineCacheUpdateParent.cpp
index a94362ebae05..8bd86a790d3a 100644
--- a/uriloader/prefetch/OfflineCacheUpdateParent.cpp
+++ b/uriloader/prefetch/OfflineCacheUpdateParent.cpp
@@ -5,14 +5,12 @@
 
 #include "OfflineCacheUpdateParent.h"
 
-#include "mozilla/dom/TabParent.h"
 #include "mozilla/ipc/URIUtils.h"
 #include "nsOfflineCacheUpdate.h"
 #include "nsIApplicationCache.h"
 #include "nsNetUtil.h"
 
 using namespace mozilla::ipc;
-using mozilla::dom::TabParent;
 
 #if defined(PR_LOGGING)
 //
@@ -45,11 +43,8 @@ NS_IMPL_ISUPPORTS2(OfflineCacheUpdateParent,
 // OfflineCacheUpdateParent <public>
 //-----------------------------------------------------------------------------
 
-OfflineCacheUpdateParent::OfflineCacheUpdateParent(uint32_t aAppId,
-                                                   bool aIsInBrowser)
+OfflineCacheUpdateParent::OfflineCacheUpdateParent()
     : mIPCClosed(false)
-    , mIsInBrowserElement(aIsInBrowser)
-    , mAppId(aAppId)
 {
     // Make sure the service has been initialized
     nsOfflineCacheUpdateService* service =
@@ -74,6 +69,8 @@ OfflineCacheUpdateParent::ActorDestroy(ActorDestroyReason why)
 nsresult
 OfflineCacheUpdateParent::Schedule(const URIParams& aManifestURI,
                                    const URIParams& aDocumentURI,
+                                   const bool& isInBrowserElement,
+                                   const uint32_t& appId,
                                    const bool& stickDocument)
 {
     LOG(("OfflineCacheUpdateParent::RecvSchedule [%p]", this));
@@ -103,7 +100,7 @@ OfflineCacheUpdateParent::Schedule(const URIParams& aManifestURI,
     if (!NS_SecurityCompareURIs(manifestURI, documentURI, false))
         return NS_ERROR_DOM_SECURITY_ERR;
 
-    service->FindUpdate(manifestURI, mAppId, mIsInBrowserElement,
+    service->FindUpdate(manifestURI, appId, isInBrowserElement,
                         getter_AddRefs(update));
     if (!update) {
         update = new nsOfflineCacheUpdate();
@@ -111,7 +108,7 @@ OfflineCacheUpdateParent::Schedule(const URIParams& aManifestURI,
         // Leave aDocument argument null. Only glues and children keep 
         // document instances.
         rv = update->Init(manifestURI, documentURI, nullptr, nullptr,
-                          mAppId, mIsInBrowserElement);
+                          appId, isInBrowserElement);
         NS_ENSURE_SUCCESS(rv, rv);
 
         rv = update->Schedule();
diff --git a/uriloader/prefetch/OfflineCacheUpdateParent.h b/uriloader/prefetch/OfflineCacheUpdateParent.h
index c2fa97450f4d..9b58e314fc84 100644
--- a/uriloader/prefetch/OfflineCacheUpdateParent.h
+++ b/uriloader/prefetch/OfflineCacheUpdateParent.h
@@ -14,10 +14,6 @@
 
 namespace mozilla {
 
-namespace dom {
-class TabParent;
-}
-
 namespace ipc {
 class URIParams;
 } // namespace ipc
@@ -38,9 +34,11 @@ public:
     nsresult
     Schedule(const URIParams& manifestURI,
              const URIParams& documentURI,
+             const bool& isInBrowserElement,
+             const uint32_t& appId,
              const bool& stickDocument);
 
-    OfflineCacheUpdateParent(uint32_t aAppId, bool aIsInBrowser);
+    OfflineCacheUpdateParent();
     ~OfflineCacheUpdateParent();
 
     virtual void ActorDestroy(ActorDestroyReason why);