FedCM and how OAuth Flows are affected in the Post-Third-Party Cookie Era

Federated identity has significantly enhanced authentication processes, providing increased security and user convenience, with the OAuth protocol being a popular choice for enabling it. Google’s Privacy Sandbox Team announced the phase-out of third-party cookies in Chrome by 2024 due to privacy concerns, prompting the introduction of Federated Consent Management (FedCM) APIs to address challenges in OAuth flows that rely on third-party cookies. FedCM allows more private sign-in methods without third-party cookies by requiring explicit user consent before contacting identity providers like Google or Facebook. To support FedCM, identity providers must integrate by providing necessary files and endpoints, while clients need to update frontend libraries. The Login Status API helps manage user login states, ensuring streamlined authentication experiences. Although FedCM is still developing and not yet a web standard, it may become essential for identity providers as browser privacy regulations evolve.