A few days ago, we wrote a post about upcoming changes to our legacy lifecycle methods, including gradual migration strategies. In React 16.3.0, we are adding a few new lifecycle methods to assist with that migration. We are also introducing new APIs for long requested features: an official context API, a ref forwarding API, and an ergonomic ref API.
Official Context API
For many years, React has offered an experimental API for context. Although it was a powerful tool, its use was discouraged because of inherent problems in the API, and because we always intended to replace the experimental API with a better one.
Version 16.3 introduces a new context API that is more efficient and supports both static type checking and deep updates.