I have been fighting with a demo for SSO and a WinForms application. I ran across this line at Single Sign-On.
SSO with Universal Login
The easiest and most secure way to implement Single Sign-on (SSO) with Auth0 is by using Universal Login for authentication. In fact, currently SSO is only possible with native platforms (like iOS or Android) if the application uses Universal Login. The Swift and Android quick starts provide some examples of using Universal Login.
Is this still the case where I can only use Universal Login for SSO with WinForms apps? Honestly, I hope so, it makes my life easier.