The at() method takes an integer value and returns the element at that index. It allows both positive and negative integers. Negative integers denote counting back from the last item in the array.
We can only use await operator within an async method. In ECMAScript 2022 we will be able to use it outside of the context of an async method in our modules.
Class fields declaration allows declaring fields, up-front making class definitions become more self-documenting. As declared fields are always present, instances go through fewer state transitions. These class fields features would be officially included in ECMAScript 2022.