[BUG] Regional Authority is not used with latest version of ClientCertificateCredential

[degant]

Library name and version

Azure.Identity 1.6.0

Describe the bug

The regional authority is not being used by the ClientCertificateCredential constructor even when it is passed in with options since it no longer passes it onto the MsalConfidentialClient ctor: link

We're trying to use the regional endpoints and this was working fine in the older versions:

• 1.5.0 - ✅ Works fine
• 1.6.0-beta1 - ✅ Works fine
• 1.6.0 - ❌ Broken

It accidentally got removed here during a refactor while the other credentials that support Regional Authority i.e ClientSecretCredential and OnBehalfOfCredential still have support for RA.

Our service can't rollback to the previous versions because we need to be on 1.6.0 which has the fix for #27679 (OBOCredentials not passing x5c)

Expected behavior

Regional Authority should work with ClientCertificateCredential just like it does with ClientSecretCredential and OnBehalfOfCredential types.

Actual behavior

Regional Authority doesn't work and calls are sent to global AAD authority instead.

Reproduction Steps

1. Create a new ClientCertificateCredential and try to pass a valid Regional Authority
2. Calls go out to global AAD instead of regional authority

Environment

No response

[jsquire]

Thank you for your feedback. Tagging and routing to the team member best able to assist.