Encode/decode text

let utf8encoder = new TextEncoder('utf-8');
console.log(utf8encoder.encode('福')); // [231, 166, 143]

let win1251decoder = new TextDecoder('windows-1251');
let bytes = new Uint8Array([207, 240, 232, 226, 229, 242, 44, 32, 236, 232, 240, 33]);
console.log(win1251decoder.decode(bytes)); // Привет, мир!