Great breakdown of React changes here: https://github.com/facebook/react/blob/master/CHANGELOG.md#0140-october-7-2015 Due to deprecation warnings, I don't think this will break third-party extensions unless they were doing really bad things.
Summary: - Also refactors the code a bit for testability and maintainability - Fixes #1515 Test Plan: - Unit tests Reviewers: evan, drew, bengotow Reviewed By: bengotow Differential Revision: https://phab.nylas.com/D2651