AZURE_REGIONAL_AUTHORITY_NAME won't work after updating to 1.6 (works in 1.5)

[sadjadbp]

I'm following the example here

var previousRegionValue = Environment.GetEnvironmentVariable("AZURE_REGIONAL_AUTHORITY_NAME");
var regionValue = Config.AzureRegion ?? RegionalAuthority.AutoDiscoverRegion;
Environment.SetEnvironmentVariable("AZURE_REGIONAL_AUTHORITY_NAME", regionValue);

var credential = new ClientCertificateCredential(tenantId, clientId, certificate,
    new ClientCertificateCredentialOptions
    {
        AuthorityHost = PublicCloudAuthority,
        SendCertificateChain = true,
    });
Environment.SetEnvironmentVariable("AZURE_REGIONAL_AUTHORITY_NAME", previousRegionValue);

With Azure.Identity 1.5+MSAL 4.44.0 it works fine and if I check credentials.Client.RegionalAuthority it is set to the AzureRegion like 'westus', but if I use Azure.Identity 1.6+MSAL 4.44.0 that credentials.Client.RegionalAuthority would be null. I have tried all below combination and looks like the only culprit is Azure.Identity 1.6

1.5+4.42.1 worked
1.5+4.43.0 worked
1.5+4.43.1 worked
1.5+4.43.2 worked
1.5+4.44.0 worked

1.6+4.42.1 didn't work
1.6+4.43.0 didn't work
1.6+4.43.1 didn't work
1.6+4.43.2 didn't work
1.6+4.44.0 didn't work

[jsquire]

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

[stowen-msft]

We seem to be seeing the same behavior as well. We are uniformly on 1.6 as well