diff --git a/step-06/js/main.js b/step-06/js/main.js
index 961f904..ea11e83 100644
--- a/step-06/js/main.js
+++ b/step-06/js/main.js
@@ -160,8 +160,10 @@ function signalingMessageCallback(message) {
 
   } else if (message.type === 'candidate') {
     peerConn.addIceCandidate(new RTCIceCandidate({
+      sdpMLineIndex: message.label,
+      sdpMid: message.id,
       candidate: message.candidate
-    }));
+    }));// Firefox compatible
 
   } else if (message === 'bye') {
 // TODO: cleanup RTC connection?