ECMAScript 2019 (ES10)

Minor new features:

arr.flat()arr.flatMap()

Object.fromEntries()

str.trimStart() str.trimEnd()

Symbol.prototype.description

try {...} catch {...} without (e) on catch

\u2028 as the paragraph separator

\u2029 as the line separator

well-formed JSON.stringify()

stable arr.sort()

revised Function.prototype.toString()