How to add allowed callaback URLs?

I am building a React Native app. I have the following Callback working:
com.company.productname://dev---1234qa.us.auth0.com/android/com.company.productname/callback

Now I want to add a callback that matches one of several variants of iOS and Android apps. The flavor builds on the existing bundle id: com.company.productname.ext where .ext is a region (e.g. ‘.us’ or ‘.eu’).

I would expect that I could do the following for the callback:
com.company.productname.ext://dev---1234qa.us.auth0.com/android/com.company.productname.ext/callback and add this to the Allowed Callback URLs. But when I do, I get the dreaded Callback URL mismatch error.

What am I doing wrong?

I’ve narrowed down the scope of what am attempting to do. Using the React Native Debugger, I have been able to ensure that I am correctly formatting the callback URLs.

Unfortunately, I am encountering the same white screen as described in Blank White Screen on redirect to Auth0 which appears to have never been resolved.

I see nothing in any logs the we are capturing to indicate what is wrong. Please advise.

Hey there @crickard thanks for the detailed description of the issue you’re experiencing - If you log in and download the sample here, do you experience the same issue?