Exception in serviceworker file (how to debug)...

Hello, I configured a FCM system for my laravel website. But I can not register the serviceworker...

TypeError: ServiceWorker script at https://localhost/firebase-messaging-sw.js for scope https://localhost/ threw an exception during script evaluation.

Here is my serviceworker code :

// Service Worker
importScripts('https://www.gstatic.com/firebasejs/10.7.1/firebase-app.js');
importScripts('https://www.gstatic.com/firebasejs/10.7.1/firebase-messaging.js');

const firebaseConfig = {
    apiKey: "****************************",
    authDomain: "***********.firebaseapp.com",
    projectId: "***********.",
    storageBucket: "***********..appspot.com",
    messagingSenderId: "***********",
    appId: "****************************",
};

firebase.initializeApp(firebaseConfig);
const messaging = firebase.getMessaging();

messaging.onBackgroundMessage(payload => {
    const notificationTitle = 'Background Message Title';
    const notificationOptions = {
        body: notificationTitle,
        icon: '<>'
    };

    self.registration.showNotification(notificationTitle, notificationOptions);
});

self.addEventListener('error', function (event) {
    console.error('Erreur dans le service worker:', event.error);
});

I do not know how to debug this code while I do not have any log.

Thanks for your help!