Interface for module auth settings.
const settings = firebase.auth().settings; console.log(settings.appVerificationDisabledForTesting);
iOS only flag to disable app verification for the purpose of testing phone authentication. For this property to take effect, it needs to be set before rendering a reCAPTCHA app verifier. When this is disabled, a mock reCAPTCHA is rendered instead. This is useful for manual testing during development or for automated integration tests.