String replaceAll() Method
WeakRef and Finalizers
Promise.any() and AggregateError
Logical Assignment Operator
let x = 1;
let y = 2;
x &&= y;
x ||= y;
x ??= y;
Underscores as Numeric Seperator
const billion = 1000_000_000;
console.log(billion); // 1000000000