Hi @Eric Hendrickson ,
Thanks for reaching out.
In Azure AD, the relay state is static and instructs the application where to redirect users after authentication is completed.
However, relay state in SP initiated flow is meant to be used as an identifier which is sent along with the SAML request to the STS and passed back to the SP without any modification or inspection, in this case it can be dynamic.
To support multiple/Dynamic RelayState URLs, your app must use SP-initiated SSO, and send the RelayState as a parameter in the SAML request as shown below, so that Azure AD can return the same information in the SAML Response.
I would suggest you post this idea at the Azure Feedback Portal, which is monitored by the product team for feature enhancements.
Hope this will help.
Thanks,
Shweta
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