Passing custom parameters through OpenIddict's client authorization request

In my passthrough authentication post , the login endpoint set a provider value on AuthenticationProperties so the OpenIddict server would know whether to challenge GitHub or ADFS: app.MapGet("login/{provider}", (string provider) => Results.Challenge(new AuthenticationProperties { RedirectUri = "/", Items = { ["provider"] = provider } }, [OpenIddictClientAspNetCoreDefaults.AuthenticationScheme]));…