This release is the first alpha release for Chai 5. The changes from v4.x: This package now uses ESM modules. CommonJS environments are no longer supported. If you wish to use a CommonJS environment, please continue to use Chai 4. Drop support for NodeJS versions less than 16. If you are using NodeJS v4-v15, please continue to use Chai 4. Drop support for Internet Explorer 10 & 11. If you wish to