code: func clear(ctx context.Context, content []byte, timeout int) error {
  	hash := fmt.Sprintf("%x", sha256.Sum256(content))
  
  	cmd := exec.CommandContext(ctx, os.Args[0], "unclip", "--timeout", strconv.Itoa(timeout))
  	cmd.Env = append(os.Environ(), "GOPASS_UNCLIP_CHECKSUM="+hash)
  	return cmd.Start()
  }
docs: // clear will spwan a copy of gopass that waits in a detached background
  // process group until the timeout is expired. It will then compare the contents
  // of the clipboard and erase it if it still contains the data gopass copied
  // to it.