[Bug] MSAL netstandard should not be excluded from mTLS

[gladjohn]

Library version used

latest

.NET version

In the lastest MSAL (4.69.1), we exclude mTLS operations from netstandard, via the SUPPORTS_MTLS feature. But HttpClientHandler.ClientCertificates underlying API is supported on NETSTANDARD. There is not reason to block this on netstandard. It will lead to "breaking" changes when we deprecate old frameworks like net6.

Scenario

ConfidentialClient - service to service (AcquireTokenForClient)

Is this a new or an existing app?

This is a new app or experiment

Issue description and reproduction steps

In the lastest MSAL (4.69.1), we exclude mTLS operations from netstandard, via the SUPPORTS_MTLS feature. But HttpClientHandler.ClientCertificates underlying API is supported on NETSTANDARD. There is not reason to block this on netstandard. It will lead to "breaking" changes when we deprecate old frameworks like net6.

Relevant code snippets

Expected behavior

Add MTLS Support to Net Standard

Identity provider

Microsoft Entra ID (Work and School accounts and Personal Microsoft accounts)

Regression

latest

Solution and workarounds

Add MTLS Support to Net Standard