message: Add a comment about alt key.
diff: @@ -125,8 +125,20 @@ export class Job extends EmitterWithUniqueID implements TerminalLikeDevice {
  text = input;
  } else {
  if (input.ctrlKey) {
  + /**
  + * @link https://unix.stackexchange.com/a/158298/201739
  + */
  text = String.fromCharCode(input.keyCode - 64);
  } else if (input.altKey) {
  + /**
  + * The alt key can mean two things:
  + * - send an escape character before special keys such as cursor-keys, or
  + * - act as an extended shift, allowing you to enter codes for Latin-1 values from 160 to 255.
  + *
  + * We currently don't support the second one since it's less frequently used.
  + * For future reference, the correct extended code would be keyCode + 160.
  + * @link http://invisible-island.net/ncurses/ncurses.faq.html#bash_meta_mode
  + */
  let char = String.fromCharCode(input.keyCode);
  if (input.shiftKey) {
  char = char.toUpperCase();
  