Logging into Facebook with Firebase: "auth / timeout" error

Question

I get the error code "auth / timeout" (message: "Operation timed out") after trying to log in using the Facebook Firebase provider with stream redirection. The error appears in getRedirectResult.catch. See code below:

getRedirectResult(): void {
    firebase.auth().getRedirectResult()
        .then(result => {
            if (result.credential) {
                let token = result.credential.accessToken;
            }
        })
        .catch(error => console.log('error on facebook login', error) );
}

I tried to log in to the computer and iPhone SE, and everything is fine. The problem only occurs in my iPad 2.