Explore the implementation of external providers in ASP.NET Core 3 and IdentityServer4 through a practical Facebook integration example in this 35-minute video tutorial. Learn how to set up and configure external authentication, enabling users to log in using their Facebook credentials. Gain insights into the process of integrating third-party authentication providers with your ASP.NET Core application, enhancing user experience and security. Follow along with the step-by-step demonstration to understand the intricacies of external provider implementation and best practices for secure authentication flows.