Redirect to Firebase Hosting custom domain

Question

I have setup a custom domain with Firebase Hosting (eg. myapp.domain.com).

How can one redirect (or turn off) the default Firebase Hosting URL (eg. myapp.firebaseap

Answer 1

In addition to specifying canonical link as mentioned in Frank van Puffelen's answer. We can also add front end JavaScript code to do the actual redirect like this without disclosing default url.

if (location.hostname.indexOf('custom.url') === -1) {
    location.replace("https://custom.url");
}