1 files changed, 3 insertions, 1 deletions

diff --git a/js/app.js b/js/app.js
index 97e671f..33a0f55 100644
--- a/js/app.js
+++ b/js/app.js
@@ -5,8 +5,10 @@ if ("serviceWorker" in navigator) {
 }
 
 // Listen to messages from service workers.
+if(navigator.serviceWorker)(
 navigator.serviceWorker.addEventListener('message', (event) => {
     if (event.data.msg === "install") {
         window.location.replace("/index.html");
     }
-});
\ No newline at end of file
+});
+)