Auth0 ACUL doesn't allow for customization of `mfa-otp-challenge`

mike.huebner
Thu, 05 Feb 2026 22:34:29 +0000

Hello!

I’m working on a very specific feature for a flow that we should only be invoking if a user is going through the MFA OTP or the MFA SMS screens. I’m looking to simply customize the screen to add a link that directs back to our website that allows us to use a third-party SDK to validate their identity.

All that to say, all I want to do is modify the mfa-otp-challenge and mfa-sms-challenge screens by adding said small link to the page. I’ve been using the auth0-cli with the acul to try and find these screen to add and so far I’ve had no luck in trying to get it working.

Within the CLI for acul I’ve ran init and add to try and find the screens and so far they don’t return anything other than the mfa-sms-challenge and mfa-email-challenge screens, which don’t seem to be what I need. However, I cannot even get them to load on the page. The only screen I’ve gotten in the login-id screen in the non-connected version.

Command:

auth0 acul dev -c -s all

Which returns an error within the console saying

Uncaught Error: Universal Login Context is not available on the global window object.

I’m unsure what I’m doing wrong as I can get the login-id screen to work without the -c command, but even specifying a screen with the -s only loads login-id. I’ve made sure to run auth0 acul screen add … for each screen I want but having no luck there either.

Please let me know if there is something I’m missing or there is something more I need to do. There is plenty of documentation about what I need to customize that is leading to 404 pages which are never helpful.