Since the Cambridge Analytica debacle, Facebook has faced pressure to improve its security practices. In response, Facebook cut the functionality of its Graph API and the Instagram API. Now, one developer has petitioned Facebook to go even further in making the Instagram API more open and secure.
CORS is a security mechanism that allows a Web page from one domain to access a resource from a different origin. This article provides an in-depth guide to Cross-Origin Resource Sharing (CORS) for REST APIs, on how CORS works, and common pitfalls especially around security.