diff --git a/cookbook/templates/offline.html b/cookbook/templates/offline.html
index dc8b63a99..404d185f7 100644
--- a/cookbook/templates/offline.html
+++ b/cookbook/templates/offline.html
@@ -28,4 +28,19 @@
         <br/>
     </div>
 
+{% endblock %}
+
+{% block script %}
+
+    <script type="application/javascript">
+
+        caches.open('html').then(productsRuntimeCache => {
+
+            productsRuntimeCache.keys().then(keys => {
+                console.log(keys)
+            });
+
+        });
+    </script>
+
 {% endblock %}
\ No newline at end of file