diff --git a/authorized-https-endpoint/public/index.html b/authorized-https-endpoint/public/index.html
index bcb36f5..3dfb57a 100644
--- a/authorized-https-endpoint/public/index.html
+++ b/authorized-https-endpoint/public/index.html
@@ -67,9 +67,12 @@
   </main>
 </div>
 
-<!-- Firebase -->
-<script src="/__/firebase/3.7.4/firebase-app.js"></script>
-<script src="/__/firebase/3.7.4/firebase-auth.js"></script>
+
+<!-- Import and configure the Firebase SDK -->
+<!-- These scripts are made available when the app is served or deployed on Firebase Hosting -->
+<!-- If you do not serve/host your project using Firebase Hosting see https://firebase.google.com/docs/web/setup -->
+<script src="/__/firebase/3.9.0/firebase-app.js"></script>
+<script src="/__/firebase/3.9.0/firebase-auth.js"></script>
 <script src="/__/firebase/init.js"></script>
 
 <script src="main.js"></script>
diff --git a/email-confirmation/public/index.html b/email-confirmation/public/index.html
index 54fb92f..0c9168e 100644
--- a/email-confirmation/public/index.html
+++ b/email-confirmation/public/index.html
@@ -96,10 +96,13 @@
   </main>
 </div>
 
-<!-- Firebase -->
-<script src="/__/firebase/3.7.4/firebase-app.js"></script>
-<script src="/__/firebase/3.7.4/firebase-auth.js"></script>
-<script src="/__/firebase/3.7.4/firebase-database.js"></script>
+
+<!-- Import and configure the Firebase SDK -->
+<!-- These scripts are made available when the app is served or deployed on Firebase Hosting -->
+<!-- If you do not serve/host your project using Firebase Hosting see https://firebase.google.com/docs/web/setup -->
+<script src="/__/firebase/3.9.0/firebase-app.js"></script>
+<script src="/__/firebase/3.9.0/firebase-auth.js"></script>
+<script src="/__/firebase/3.9.0/firebase-database.js"></script>
 <script src="/__/firebase/init.js"></script>
 
 <script src="main.js"></script>
diff --git a/exif-images/public/index.html b/exif-images/public/index.html
index e3ba53a..959a1a8 100644
--- a/exif-images/public/index.html
+++ b/exif-images/public/index.html
@@ -61,11 +61,14 @@ limitations under the License.
     </main>
   </div>
 
-  <!-- Firebase -->
-  <script src="/__/firebase/3.7.4/firebase-app.js"></script>
-  <script src="/__/firebase/3.7.4/firebase-auth.js"></script>
-  <script src="/__/firebase/3.7.4/firebase-storage.js"></script>
-  <script src="/__/firebase/3.7.4/firebase-database.js"></script>
+
+  <!-- Import and configure the Firebase SDK -->
+  <!-- These scripts are made available when the app is served or deployed on Firebase Hosting -->
+  <!-- If you do not serve/host your project using Firebase Hosting see https://firebase.google.com/docs/web/setup -->
+  <script src="/__/firebase/3.9.0/firebase-app.js"></script>
+  <script src="/__/firebase/3.9.0/firebase-auth.js"></script>
+  <script src="/__/firebase/3.9.0/firebase-storage.js"></script>
+  <script src="/__/firebase/3.9.0/firebase-database.js"></script>
   <script src="/__/firebase/init.js"></script>
 
   <script src="main.js"></script>
diff --git a/fcm-notifications/public/index.html b/fcm-notifications/public/index.html
index 01ee962..bef5bd5 100644
--- a/fcm-notifications/public/index.html
+++ b/fcm-notifications/public/index.html
@@ -82,11 +82,14 @@
   </main>
 </div>
 
-<!-- Firebase -->
-<script src="/__/firebase/3.7.4/firebase-app.js"></script>
-<script src="/__/firebase/3.7.4/firebase-auth.js"></script>
-<script src="/__/firebase/3.7.4/firebase-messaging.js"></script>
-<script src="/__/firebase/3.7.4/firebase-database.js"></script>
+
+<!-- Import and configure the Firebase SDK -->
+<!-- These scripts are made available when the app is served or deployed on Firebase Hosting -->
+<!-- If you do not serve/host your project using Firebase Hosting see https://firebase.google.com/docs/web/setup -->
+<script src="/__/firebase/3.9.0/firebase-app.js"></script>
+<script src="/__/firebase/3.9.0/firebase-auth.js"></script>
+<script src="/__/firebase/3.9.0/firebase-messaging.js"></script>
+<script src="/__/firebase/3.9.0/firebase-database.js"></script>
 <script src="/__/firebase/init.js"></script>
 
 <script src="main.js"></script>
diff --git a/instagram-auth/public/index.html b/instagram-auth/public/index.html
index 5b8d91f..98cc4f2 100644
--- a/instagram-auth/public/index.html
+++ b/instagram-auth/public/index.html
@@ -67,9 +67,12 @@
   </main>
 </div>
 
-<!-- Firebase -->
-<script src="/__/firebase/3.7.4/firebase-app.js"></script>
-<script src="/__/firebase/3.7.4/firebase-auth.js"></script>
+
+<!-- Import and configure the Firebase SDK -->
+<!-- These scripts are made available when the app is served or deployed on Firebase Hosting -->
+<!-- If you do not serve/host your project using Firebase Hosting see https://firebase.google.com/docs/web/setup -->
+<script src="/__/firebase/3.9.0/firebase-app.js"></script>
+<script src="/__/firebase/3.9.0/firebase-auth.js"></script>
 <script src="/__/firebase/init.js"></script>
 
 <script src="main.js"></script>
diff --git a/instagram-auth/public/popup.html b/instagram-auth/public/popup.html
index a3a822a..7d43cf1 100644
--- a/instagram-auth/public/popup.html
+++ b/instagram-auth/public/popup.html
@@ -23,9 +23,12 @@
 
 Please wait...
 
-<!-- Firebase -->
-<script src="/__/firebase/3.7.4/firebase-app.js"></script>
-<script src="/__/firebase/3.7.4/firebase-auth.js"></script>
+
+<!-- Import and configure the Firebase SDK -->
+<!-- These scripts are made available when the app is served or deployed on Firebase Hosting -->
+<!-- If you do not serve/host your project using Firebase Hosting see https://firebase.google.com/docs/web/setup -->
+<script src="/__/firebase/3.9.0/firebase-app.js"></script>
+<script src="/__/firebase/3.9.0/firebase-auth.js"></script>
 <script src="/__/firebase/init.js"></script>
 
 <script>
diff --git a/linkedin-auth/public/index.html b/linkedin-auth/public/index.html
index 35d47fe..1cd8365 100644
--- a/linkedin-auth/public/index.html
+++ b/linkedin-auth/public/index.html
@@ -68,9 +68,12 @@
   </main>
 </div>
 
-<!-- Firebase -->
-<script src="/__/firebase/3.7.4/firebase-app.js"></script>
-<script src="/__/firebase/3.7.4/firebase-auth.js"></script>
+
+<!-- Import and configure the Firebase SDK -->
+<!-- These scripts are made available when the app is served or deployed on Firebase Hosting -->
+<!-- If you do not serve/host your project using Firebase Hosting see https://firebase.google.com/docs/web/setup -->
+<script src="/__/firebase/3.9.0/firebase-app.js"></script>
+<script src="/__/firebase/3.9.0/firebase-auth.js"></script>
 <script src="/__/firebase/init.js"></script>
 
 <script src="main.js"></script>
diff --git a/linkedin-auth/public/popup.html b/linkedin-auth/public/popup.html
index a202749..a265d44 100644
--- a/linkedin-auth/public/popup.html
+++ b/linkedin-auth/public/popup.html
@@ -23,9 +23,12 @@
 
 Please wait...
 
-<!-- Firebase -->
-<script src="/__/firebase/3.7.4/firebase-app.js"></script>
-<script src="/__/firebase/3.7.4/firebase-auth.js"></script>
+
+<!-- Import and configure the Firebase SDK -->
+<!-- These scripts are made available when the app is served or deployed on Firebase Hosting -->
+<!-- If you do not serve/host your project using Firebase Hosting see https://firebase.google.com/docs/web/setup -->
+<script src="/__/firebase/3.9.0/firebase-app.js"></script>
+<script src="/__/firebase/3.9.0/firebase-auth.js"></script>
 <script src="/__/firebase/init.js"></script>
 
 <script>
diff --git a/text-moderation/public/index.html b/text-moderation/public/index.html
index 9e93129..197fb30 100644
--- a/text-moderation/public/index.html
+++ b/text-moderation/public/index.html
@@ -90,9 +90,12 @@
   </main>
 </div>
 
-<!-- Firebase -->
-<script src="/__/firebase/3.7.4/firebase-app.js"></script>
-<script src="/__/firebase/3.7.4/firebase-database.js"></script>
+
+<!-- Import and configure the Firebase SDK -->
+<!-- These scripts are made available when the app is served or deployed on Firebase Hosting -->
+<!-- If you do not serve/host your project using Firebase Hosting see https://firebase.google.com/docs/web/setup -->
+<script src="/__/firebase/3.9.0/firebase-app.js"></script>
+<script src="/__/firebase/3.9.0/firebase-database.js"></script>
 <script src="/__/firebase/init.js"></script>
 
 <script src="main.js"></script>
diff --git a/user-data-cleanup/public/index.html b/user-data-cleanup/public/index.html
index c1e46f4..776b449 100644
--- a/user-data-cleanup/public/index.html
+++ b/user-data-cleanup/public/index.html
@@ -67,10 +67,12 @@
   </main>
 </div>
 
-<!-- Firebase -->
-<script src="/__/firebase/3.7.4/firebase-app.js"></script>
-<script src="/__/firebase/3.7.4/firebase-auth.js"></script>
-<script src="/__/firebase/3.7.4/firebase-database.js"></script>
+<!-- Import and configure the Firebase SDK -->
+<!-- These scripts are made available when the app is served or deployed on Firebase Hosting -->
+<!-- If you do not serve/host your project using Firebase Hosting see https://firebase.google.com/docs/web/setup -->
+<script src="/__/firebase/3.9.0/firebase-app.js"></script>
+<script src="/__/firebase/3.9.0/firebase-auth.js"></script>
+<script src="/__/firebase/3.9.0/firebase-database.js"></script>
 <script src="/__/firebase/init.js"></script>
 
 <script src="main.js"></script>