JWT Decoder written in TypeScript [pasted]

index.ts

const decodeJWT = (token: string): string =>
    decodeURIComponent(
      atob(token.split(".")[1].replace("-", "+").replace("_", "/"))
        .split("")
        .map((c) => `%${("00" + c.charCodeAt(0).toString(16)).slice(-2)}`)
        .join("")
    );

console.log(
    decodeJwt(`
        eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.
        eyJzdWIiOiIxMjM0NTY3ODkwIiwibmFtZSI6IkpvaG4gRG9lIiwiaWF0I
        joxNTE2MjM5MDIyfQ.SflKxwRJSMeKKF2QT4fwpMeJf36POk6yJV_adQssw5c
    `)
)