diff --git a/index-dev.html b/index-dev.html
index 85d5d488..32883e2b 100644
--- a/index-dev.html
+++ b/index-dev.html
@@ -29,13 +29,13 @@
     <!-- Styles for local elements -->
     <link rel="stylesheet" href="css/base.css" />
     <!-- ReactJS -->
-    <script crossorigin="anonymous" src="https://unpkg.com/react@16/umd/react.development.js"></script>
-    <script crossorigin="anonymous" src="https://unpkg.com/react-dom@16/umd/react-dom.development.js"></script>
+    <script crossorigin="anonymous" src="https://cdn.jsdelivr.net/npm/react@16/umd/react.development.js"></script>
+    <script crossorigin="anonymous" src="https://cdn.jsdelivr.net/npm/react-dom@16/umd/react-dom.development.js"></script>
     <!-- React-Intl for translations -->
-    <script crossorigin="anonymous" src="https://unpkg.com/react-intl@3/dist/react-intl.js"></script>
+    <script crossorigin="anonymous" src="https://cdn.jsdelivr.net/npm/react-intl@3/dist/react-intl.js"></script>
     <!-- Firebase for push notifications -->
-    <script crossorigin="anonymous" src="https://unpkg.com/firebase@6.4.2/firebase-app.js"></script>
-    <script crossorigin="anonymous" src="https://unpkg.com/firebase@6.4.2/firebase-messaging.js"></script>
+    <script crossorigin="anonymous" src="https://cdn.jsdelivr.net/npm/firebase@6.6.2/firebase-app.js"></script>
+    <script crossorigin="anonymous" src="https://cdn.jsdelivr.net/npm/firebase@6.6.2/firebase-messaging.js"></script>
   </head>
 
   <body>
diff --git a/index.html b/index.html
index ff7038d4..e6d28add 100644
--- a/index.html
+++ b/index.html
@@ -22,11 +22,11 @@
 <link rel="stylesheet" href="https://fonts.googleapis.com/css?family=Roboto:300,400,400i,500,700,700i" />
 <link rel="stylesheet" href="https://fonts.googleapis.com/icon?family=Material+Icons" />
 <link rel="stylesheet" href="css/base.min.css" />
-<script crossorigin="anonymous" src="https://unpkg.com/react@16.9.0/umd/react.production.min.js"></script>
-<script crossorigin="anonymous" src="https://unpkg.com/react-dom@16.9.0/umd/react-dom.production.min.js"></script>
-<script crossorigin="anonymous" src="https://unpkg.com/react-intl@3.3.0/dist/react-intl.min.js"></script>
-<script crossorigin="anonymous" src="https://unpkg.com/firebase@6.4.2/firebase-app.js"></script>
-<script crossorigin="anonymous" src="https://unpkg.com/firebase@6.4.2/firebase-messaging.js"></script>
+<script crossorigin="anonymous" src="https://cdn.jsdelivr.net/npm/react@16.9.0/umd/react.production.min.js"></script>
+<script crossorigin="anonymous" src="https://cdn.jsdelivr.net/npm/react-dom@16.9.0/umd/react-dom.production.min.js"></script>
+<script crossorigin="anonymous" src="https://cdn.jsdelivr.net/npm/react-intl@3.3.0/dist/react-intl.min.js"></script>
+<script crossorigin="anonymous" src="https://cdn.jsdelivr.net/npm/firebase@6.6.2/firebase-app.js"></script>
+<script crossorigin="anonymous" src="https://cdn.jsdelivr.net/npm/firebase@6.6.2/firebase-messaging.js"></script>
 </head>
 <body>
 <noscript><div id="noscript-message"><div id="noscript-title">Javascript support is required.</div>
diff --git a/service-worker.js b/service-worker.js
index 0e6fc247..e4801593 100644
--- a/service-worker.js
+++ b/service-worker.js
@@ -1,6 +1,6 @@
 // Must be located at the root.
-importScripts('https://unpkg.com/firebase@6.4.2/firebase-app.js');
-importScripts('https://unpkg.com/firebase@6.4.2/firebase-messaging.js');
+importScripts('https://cdn.jsdelivr.net/npm/firebase@6.6.2/firebase-app.js');
+importScripts('https://cdn.jsdelivr.net/npm/firebase@6.6.2/firebase-messaging.js');
 importScripts('firebase-init.js');
 
 firebase.initializeApp(FIREBASE_INIT);