Angular Does ngOnDestroy run inside the service?

I have a service this service should run until the project is started and closed. After the application (website) is closed, the ngOnDestroy() method of the service should run. How do I know if the ngOnDestroy() method in the service is working? Does this ngOnDestroy() work?

export class UserServiceService implements OnDestroy {
subsc: Subscription;

constructor(
private auth: AngularFireAuth,
private db: AngularFireDatabase,
private fnc: AngularFireFunctions,
private router: Router,
private tostr: ToastrService,
) {
this.subsc = this.auth.authState.subscribe((user) => {
if (user) {
this.db.database
.ref("users/" + user.uid + "/shopCart/")
.on("value", (snap) => {});
} else {
//not user
}
});
}

ngOnDestroy(): void {
console.log("Closed");
this.subsc.unsubscribe();
this.db.database.ref("users/" + this.currentUserId + "/shopCart/").off();
}
}

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