diff --git a/static/demos/light-dark-demo-4/sw.js b/static/demos/light-dark-demo-4/sw.js
index 4ed3097..d4f06bc 100644
--- a/static/demos/light-dark-demo-4/sw.js
+++ b/static/demos/light-dark-demo-4/sw.js
@@ -34,8 +34,9 @@ async function handle_redirect(req){
             transaction.oncomplete = res;
 
             transaction.objectStore("light-dark-store", "readwrite");
-            toggleLightDark(transaction);
-            transaction.commit();
+            toggleLightDark(transaction)
+                .then(transaction.commit.bind(transaction))
+                .then(res);
         };
     });
     await Promise.all([up_promise, suc_promise]);