ES7

JavaScript Array.prototype.includes

["Banana", "Orange", "Apple", "Mango"].includes("Mango"); // is true

Exponentiation Operator

let z = 5 ** 2; // 25
let y = Math.pow(5, 2); // 25

Exponentiation Assignment

let z = 5;
z **= 2; // 25

ref

What Else?
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