1. String.prototype.padStart(), String.prototype.padEnd()

    The `padStart()` and `padEnd()` methods pad the current string with a given string (eventually repeated) so that the resulting string reaches a given length. The pad is applied from the start (left) of the current string for `padStart()`, and applied from the end (right) of the current string for `padEnd()`.

  2. javascript built-in: string: padstart