Or if anyone else can assist…
I have a very standard Application with SAML Addon enable to act as a SAML IDP.
The login_hint is definitely being provided to the endpoint defined in the SAML metadata (as provided to the SP), however this is simply being thrown away by the redirection, and email address is not prefilled.
https://CUSTOM_DOMAIN/samlp/ID?SAMLRequest=SAML_REQUEST&RelayState=RELAY_STATE&login_hint=EMAIL_ADDRESS
(HTTP 302) →
/u/login/identifier?state=STATE
I have searched for hours to find an answer to this with no luck… hope someone has solved this already because it seems like such a basic and obvious feature which should “just work”.