Bug 801257 - System Message API: Page would wrongly handle messages to be sent to other pages. r=fabrice

dom/messages/SystemMessageManager.js

@@ -174,8 +174,9 @@ SystemMessageManager.prototype = {
           " (" + this._manifest + ")");
 
     let msg = aMessage.json;
-    if (msg.manifest != this._manifest)
+    if (msg.manifest != this._manifest || msg.uri != this._uri) {
       return;
+    }
 
     // Send an acknowledgement to parent to clean up the pending message,
     // so a re-launched app won't handle it again, which is redundant.