There are several hundred million active personal Microsoft account holders using different services such as Outlook, OneDrive, Xbox Live, and Microsoft 365. At Build 2023, Microsoft announced Microsoft Quick Authentication library that allows developers to easily add Sign in with Microsoft support. With this, users can sign up and sign into apps and websites using their existing Microsoft Account (MSA).
Microsoft Quick Authentication allows developers to just drop a small snippet of HTML (or JavaScript) into their site to create a sign-in button or prompt for MSA holders. When they click to sign in, Microsoft’s code will securely authenticate them and provide the necessary details for developers to sign them in (or register them for a new account).
Even though Quick Authentication is a cross-browser solution, it delivers an enhanced user experience in Microsoft Edge when the user’s browser profile is an MSA. These Edge users will have a personalized sign in prompt that incorporates their account information.
Microsoft offers sample code for different platforms, find the source link below for details.