--- a/netwerk/protocol/http/HttpBaseChannel.cpp
+++ b/netwerk/protocol/http/HttpBaseChannel.cpp
@@ -3243,16 +3243,22 @@ HttpBaseChannel::SetupReplacementChannel
                                     oldAcceptValue,
                                     false);
     }
   }
 
   // share the request context - see bug 1236650
   httpChannel->SetRequestContextID(mRequestContextID);
 
+  // Preserve the loading order
+  nsCOMPtr<nsISupportsPriority> p = do_QueryInterface(newChannel);
+  if (p) {
+    p->SetPriority(mPriority);
+  }
+
   if (httpInternal) {
     // Convey third party cookie, conservative, and spdy flags.
     httpInternal->SetThirdPartyFlags(mThirdPartyFlags);
     httpInternal->SetAllowSpdy(mAllowSpdy);
     httpInternal->SetAllowAltSvc(mAllowAltSvc);
     httpInternal->SetBeConservative(mBeConservative);
 
     RefPtr<nsHttpChannel> realChannel;