ECMAScript 2015 support in Mozilla - Archive of obsolete content | MDNThis is an archived page. It's not actively maintained. ECMAScript 2015 is the sixth edition of the ECMAScript Language Specification standard. It defines the standard for the JavaScript implementation in SpiderMonkey, the engine used in Firefox and other Mozilla applications. Code-named "ES.next", "Harmony", or "ECMAScript 6", the first working draft (based on ECMAScript 5.1) was published on Jul
