Add domain + add extension id for firefox

package.json

@@ -48,6 +48,11 @@
     ],
     "host_permissions": [
       "<all_urls>"
-    ]
+    ],
+    "browser_specific_settings": {
+      "gecko": {
+        "id": "3fd86354-c73f-4395-9e26-2c5c984579bf"
+      }
+    }
   }
 }