diff --git a/package.json b/package.json
index d52b088..a069462 100644
--- a/package.json
+++ b/package.json
@@ -7,9 +7,9 @@
   "bugs": {
     "url": "https://github.com/mozilla/testpilot-containers/issues"
   },
-  "dependencies": {
-  },
+  "dependencies": {},
   "devDependencies": {
+    "addons-linter": "^0.15.14",
     "eslint": "^3.12.2",
     "jpm": "^1.2.2"
   },
diff --git a/webextension/manifest.json b/webextension/manifest.json
index 150f073..54e137d 100644
--- a/webextension/manifest.json
+++ b/webextension/manifest.json
@@ -21,8 +21,7 @@
 
   "permissions": [
     "cookies",
-    "tabs",
-    "cookies"
+    "tabs"
   ],
 
   "browser_action": {