Download Yahoo Mail app and setup. They call their MFA Account Key and it uses the Mail app to push similar to Duo. I think other apps include Account Key, bu

Download Yahoo Mail app and setup. They call their MFA Account Key and it uses the Mail app to push similar to Duo. I think other apps include Account Key, but it was just being pushed out when I last worked with Yahoo. The SMS is just a bootstrap and once you have the app you can pick your second authenticator as login.