diff --git a/src/Twig/PwaRuntime.php b/src/Twig/PwaRuntime.php
index 0792016..dc9d4de 100644
--- a/src/Twig/PwaRuntime.php
+++ b/src/Twig/PwaRuntime.php
@@ -102,6 +102,7 @@ private function injectServiceWorker(string $output, bool $injectSW, array $swAt
   if ('serviceWorker' in navigator) {
     const wb = new Workbox('{$url}'{$registerOptions});
     wb.register();
+    window.workbox = wb;
   }
 </script>
 SERVICE_WORKER;