How to test production custom domain at UAT

Hello guys,

I’m using embedded login with a custom domain. I have a custom domain set up in my auth0 production tenant. The custom domain is set like https://login.mydomain.com/ also I have a production app hosted at https://mydomain.com.

I wonder how can I test at UAT the custom domain set in my production tenant if the UAT app is hosted at http://uat.mydomain.com?

Please advise.