Passwordless on Android: Stuck at "Cannot GET /wsfed?..."

In a full OIDC conformant system, how would we go about having true password less login on Android?

=> Says Passwordless is disabled by default, but refers to Lock Passwordless on Auth0’s Hosted Login Page
Following that link (Auth0 Universal Login), I get the info:

Passwordless on Native Platforms

Currently, the Hosted Login Page is the only way to use Passwordless authentication on Native platforms. So if your use case is a native iOS or Android application, for example, and you intend to implement Passwordless, you will need to use the Hosted Login Page.

Choose a technology, I will choose the Lock Passwordless first: Auth0 Universal Login

However, the link won’t be activated. I learn later that the Hosted Login Page on Android can be done with the Auth0 WebAuthProvider class only, but I need to configure that page like so Auth0 Universal Login

That seems ok, testing it works, now for Android:

I configure the AndroidManifest.xml:

    <intent-filter android:autoVerify="true">
        <action android:name="android.intent.action.VIEW"/>

        <category android:name="android.intent.category.DEFAULT"/>
        <category android:name="android.intent.category.BROWSABLE"/>


Now I run this in my Login Activity, expecting a new window with the login page (and the input field for email address):

protected void btnEmailClicked() {
                   .withScope("openid email profile")
                   .start(this, authCallback);

But nope, I will get a new page with contents:

“Cannot GET /wsfed?..” … long link.

What am I doing wrong here?

Did you eve solve this?