Angularfire2: How to retrieve file content from Firebase storage

I am developing an Ionic application using Angulfire2.

I have successfully uploaded files to Firebase.

I found that the method getDownloadURL retrieves the file URL and it displays fine in the HTML page.

However, I can't find a way to download the content of the file. I am trying to perform an http request like this:

let headers = new HttpHeaders({ "Content-Type": "image/png" });
let imageGet = this.http.get(firestorageImageURI, { headers: headers }).subscribe((response) => {
    debugger;
});

But I got CORS error in console:

Access XMLHttpRequest via 'https://firebasestorage.googleapis.com/v0/b/xxxx.appspot.com/o/edls%2Fb2478a2b-48eb-4056-94c8-e83d858cd519%2Fb2478a2b-48eb-4056-94c8-e83d858cd519_b_1603046492694. 'alt=media&token=8ce76185-dd05-451e-919e-49f695145237' from alt has been blocked by CORS policy: No 'Access-Control-Allow-Origin' header on the requested resource.

I also configured CORS to allow all origins as detailed here : https://firebase.google.com/docs/storage/web/download-files

But it didn't change the error.

I also changed the storage rule to:

rules_version = '2'; 
service firebase.storage {   
  match /b/{bucket}/o {
     match /{allPaths=**} {
          allow read, write: if true;
     }   
  } 
}

Does anyone know how to download files from Firebase Storage using angularfire2?

thanks in advance