diff --git a/dom/base/nsGkAtomList.h b/dom/base/nsGkAtomList.h
index a03d99c038fe..71e816617056 100644
--- a/dom/base/nsGkAtomList.h
+++ b/dom/base/nsGkAtomList.h
@@ -920,7 +920,6 @@ GK_ATOM(onloadingerror, "onloadingerror")
 GK_ATOM(onpopstate, "onpopstate")
 GK_ATOM(only, "only")               // this one is not an event
 GK_ATOM(onmessage, "onmessage")
-GK_ATOM(onmessageerror, "onmessageerror")
 GK_ATOM(onmousedown, "onmousedown")
 GK_ATOM(onmouseenter, "onmouseenter")
 GK_ATOM(onmouseleave, "onmouseleave")
diff --git a/dom/messagechannel/MessagePort.cpp b/dom/messagechannel/MessagePort.cpp
index b28dfd4e7527..aaf3ef0ef373 100644
--- a/dom/messagechannel/MessagePort.cpp
+++ b/dom/messagechannel/MessagePort.cpp
@@ -137,7 +137,6 @@ private:
     }
 
     if (NS_WARN_IF(rv.Failed())) {
-      mPort->DispatchError();
       return rv.StealNSResult();
     }
 
@@ -149,7 +148,6 @@ private:
 
     Sequence<OwningNonNull<MessagePort>> ports;
     if (!mData->TakeTransferredPortsAsSequence(ports)) {
-      mPort->DispatchError();
       return NS_ERROR_OUT_OF_MEMORY;
     }
 
@@ -696,7 +694,7 @@ MessagePort::Entangled(nsTArray<ClonedMessageData>& aMessages)
   FallibleTArray<RefPtr<SharedMessagePortMessage>> data;
   if (NS_WARN_IF(!SharedMessagePortMessage::FromMessagesToSharedChild(aMessages,
                                                                       data))) {
-    DispatchError();
+    // OOM, we cannot continue.
     return;
   }
 
@@ -750,7 +748,7 @@ MessagePort::MessagesReceived(nsTArray<ClonedMessageData>& aMessages)
   FallibleTArray<RefPtr<SharedMessagePortMessage>> data;
   if (NS_WARN_IF(!SharedMessagePortMessage::FromMessagesToSharedChild(aMessages,
                                                                       data))) {
-    DispatchError();
+    // OOM, We cannot continue.
     return;
   }
 
@@ -1006,28 +1004,5 @@ MessagePort::ForceClose(const MessagePortIdentifier& aIdentifier)
   ForceCloseHelper::ForceClose(aIdentifier);
 }
 
-void
-MessagePort::DispatchError()
-{
-  nsCOMPtr<nsIGlobalObject> globalObject = GetParentObject();
-
-  AutoJSAPI jsapi;
-  if (!globalObject || !jsapi.Init(globalObject)) {
-    NS_WARNING("Failed to initialize AutoJSAPI object.");
-    return;
-  }
-
-  RootedDictionary<MessageEventInit> init(jsapi.cx());
-  init.mBubbles = false;
-  init.mCancelable = false;
-
-  RefPtr<Event> event =
-    MessageEvent::Constructor(this, NS_LITERAL_STRING("messageerror"), init);
-  event->SetTrusted(true);
-
-  bool dummy;
-  DispatchEvent(event, &dummy);
-}
-
 } // namespace dom
 } // namespace mozilla
diff --git a/dom/messagechannel/MessagePort.h b/dom/messagechannel/MessagePort.h
index 00ad02a79004..4ca51353dee8 100644
--- a/dom/messagechannel/MessagePort.h
+++ b/dom/messagechannel/MessagePort.h
@@ -74,8 +74,6 @@ public:
 
   void SetOnmessage(EventHandlerNonNull* aCallback);
 
-  IMPL_EVENT_HANDLER(messageerror)
-
   // Non WebIDL methods
 
   void UnshippedEntangle(MessagePort* aEntangledPort);
@@ -149,8 +147,6 @@ private:
   // Dispatch events from the Message Queue using a nsRunnable.
   void Dispatch();
 
-  void DispatchError();
-
   void StartDisentangling();
   void Disentangle();
 
diff --git a/dom/webidl/MessagePort.webidl b/dom/webidl/MessagePort.webidl
index df19470742a9..6495b5616de7 100644
--- a/dom/webidl/MessagePort.webidl
+++ b/dom/webidl/MessagePort.webidl
@@ -17,6 +17,5 @@ interface MessagePort : EventTarget {
 
   // event handlers
   attribute EventHandler onmessage;
-  attribute EventHandler onmessageerror;
 };
 // MessagePort implements Transferable;