How can I set up B2C to send the user's email address instead of their object ID when using SAML?

[LachlanWintour]

Hi all,

I have recently successfully set up AAD B2C with a SAML application, and all is working fine.

However, B2C sends the user's object ID back to my application, and we would like B2C to send the user's email address instead.

Is this something that can be done? If so, how do we achieve this?

We are using custom policies in our B2C deployment.

Thanks in advance,

Lachlan