ES.Next is a dynamic name that refers to whatever the next version is at time of writing. ES.Next features are more correctly called proposals, because, by definition, the specification has not been finalized yet. Many features that are a “part” of ES.Next were not even proposed during the work on ES6. Indeed, as a living language, ECMAScript / JavaScript is constantly evolving and being enhanced, and new proposals are continuously being added into ES.Next.
ES Next simply call the Next version or upcoming version of ES(ECMAScript / JavaScript ). ES Next is the underdevelopment version or beta version. When completing the version and replace a new name like ES 2020/2021
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