diff --git a/dom/base/ProcessGlobal.cpp b/dom/base/ProcessGlobal.cpp
index e19cc0871651..8549bc4be4c8 100644
--- a/dom/base/ProcessGlobal.cpp
+++ b/dom/base/ProcessGlobal.cpp
@@ -96,11 +96,10 @@ NS_IMPL_CYCLE_COLLECTION_UNLINK_END
 
 NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(ProcessGlobal)
   NS_WRAPPERCACHE_INTERFACE_MAP_ENTRY
-  NS_INTERFACE_MAP_ENTRY_AMBIGUOUS(nsISupports, nsIContentProcessMessageManager)
+  NS_INTERFACE_MAP_ENTRY_AMBIGUOUS(nsISupports, nsIMessageManagerGlobal)
   NS_INTERFACE_MAP_ENTRY(nsIMessageListenerManager)
   NS_INTERFACE_MAP_ENTRY(nsIMessageSender)
   NS_INTERFACE_MAP_ENTRY(nsISyncMessageSender)
-  NS_INTERFACE_MAP_ENTRY(nsIContentProcessMessageManager)
   NS_INTERFACE_MAP_ENTRY(nsIScriptObjectPrincipal)
   NS_INTERFACE_MAP_ENTRY(nsIGlobalObject)
   NS_INTERFACE_MAP_ENTRY(nsISupportsWeakReference)
diff --git a/dom/base/ProcessGlobal.h b/dom/base/ProcessGlobal.h
index 5544166dba42..71391c3c23bf 100644
--- a/dom/base/ProcessGlobal.h
+++ b/dom/base/ProcessGlobal.h
@@ -26,7 +26,7 @@ namespace mozilla {
 namespace dom {
 
 class ProcessGlobal :
-  public nsIContentProcessMessageManager,
+  public nsIMessageManagerGlobal,
   public nsMessageManagerScriptExecutor,
   public nsIGlobalObject,
   public nsIScriptObjectPrincipal,
@@ -52,7 +52,7 @@ public:
   static ProcessGlobal* Get();
 
   NS_DECL_CYCLE_COLLECTING_ISUPPORTS
-  NS_DECL_CYCLE_COLLECTION_SCRIPT_HOLDER_CLASS_AMBIGUOUS(ProcessGlobal, nsIContentProcessMessageManager)
+  NS_DECL_CYCLE_COLLECTION_SCRIPT_HOLDER_CLASS_AMBIGUOUS(ProcessGlobal, nsIMessageManagerGlobal)
 
   virtual JSObject* WrapObject(JSContext* aCx,
                                JS::Handle<JSObject*> aGivenProto) override
@@ -93,7 +93,6 @@ public:
   NS_FORWARD_SAFE_NSIMESSAGESENDER(mMessageManager)
   NS_FORWARD_SAFE_NSISYNCMESSAGESENDER(mMessageManager)
   NS_FORWARD_SAFE_NSIMESSAGEMANAGERGLOBAL(mMessageManager)
-  NS_FORWARD_SAFE_NSICONTENTPROCESSMESSAGEMANAGER(mMessageManager)
 
   virtual void LoadScript(const nsAString& aURL);
 
diff --git a/dom/base/nsCCUncollectableMarker.cpp b/dom/base/nsCCUncollectableMarker.cpp
index 0209a05358e3..7f0140988819 100644
--- a/dom/base/nsCCUncollectableMarker.cpp
+++ b/dom/base/nsCCUncollectableMarker.cpp
@@ -477,9 +477,9 @@ mozilla::dom::TraceBlackJS(JSTracer* aTrc, bool aIsShutdownGC)
   }
 
   if (nsFrameMessageManager::GetChildProcessManager()) {
-    nsIContentProcessMessageManager* pg = ProcessGlobal::Get();
+    ProcessGlobal* pg = ProcessGlobal::Get();
     if (pg) {
-      mozilla::TraceScriptHolder(pg, aTrc);
+      mozilla::TraceScriptHolder(ToSupports(pg), aTrc);
     }
   }
 
diff --git a/dom/base/nsIMessageManager.idl b/dom/base/nsIMessageManager.idl
index 098d238c497c..abc502285b5e 100644
--- a/dom/base/nsIMessageManager.idl
+++ b/dom/base/nsIMessageManager.idl
@@ -424,17 +424,6 @@ interface nsIInProcessContentFrameMessageManager : nsIContentFrameMessageManager
   [notxpcom] void cacheFrameLoader(in nativeFrameLoader aFrameLoader);
 };
 
-[uuid(6d12e467-2446-46db-9965-e4e93cb87ca5)]
-interface nsIContentProcessMessageManager : nsIMessageManagerGlobal
-{
-  /**
-   * Read out a copy of the object that was initialized in the parent
-   * process via nsIProcessScriptLoader.initialProcessData.
-   */
-  [implicit_jscontext]
-  readonly attribute jsval initialProcessData;
-};
-
 [uuid(bf61446b-ba24-4b1d-88c7-4f94724b9ce1)]
 interface nsIFrameScriptLoader : nsISupports
 {