Code:
F1 {
  if ($me ison $active) {
    if $query(1) { window -a $v1 }
    return
  }
  if (!$query($active)) { return }
  var %i = 1 | while ($query(%i) != $active) { inc %i }
  close -m $active
  if ($query(%i) || $query(1)) { window -a $v1 }
  else shift 1
}