diff --git a/src/service-worker.js b/src/service-worker.js
index 4846f63..314e0c8 100644
--- a/src/service-worker.js
+++ b/src/service-worker.js
@@ -40,7 +40,7 @@ workbox.routing.registerRoute(
     'https://jspm.dev',
     'https://fonts.googleapis.com',
     'https://cdn.startinblox.com'
-  ].includes(url.origin) || url.origin.test(/cdn/),
+  ].includes(url.origin) || /cdn/.test(url.origin),
   new workbox.strategies.StaleWhileRevalidate({
     cacheName: 'cdn',
   })