Saml <Subject> from AuthnRequest
Allow rps to specify a saml <Subject>. When the rp knows the user adfs could then pre populate the username field on the login page.
Kim Hjort commented
It's hard to specify what querystrings a relaying party trust is sending, when not in control.
Seems like more and more are using this saml <subject> in AuthnRequest...
Samuel Devasahayam [MSFT] commented
Interesting. We support this if you send query parameters &username= or &login_hint= today. AAD uses this to send this to ADFS. It should work over SAML protocol as well.