Quick snippet to see who is also with you in where :)

; usage /comchandlg
dialog _comchandlg {
  title "Common Channels"
  size -1 -1 230 231
  option pixels notheme
  text "Channel:", 1, 12 13 53 17
  combo 2, 73 12 152 260, drop
  list 3, 6 39 101 157
  button "Close", 7, 6 193 213 31, ok
  list 4, 121 39 101 157
}

alias comchandlg {
  dialog -mo _comchandlg _comchandlg
}

on *:DIALOG:_comchandlg:init:0:{
  var %i = 0
  while (%i < $chan(0)) {
    inc %i
    did -a $dname 2 $chan(%i)
  }
  did -c $dname 2 1
  var %chan = $did(2,1)
  _getComChans %chan
}
on *:DIALOG:_comchandlg:sclick:*:{
  if ($did == 2) {
    did -r $dname 4
    _getComChans $did(2).seltext
  }
  if ($did == 3) {
    did -r $dname 4
    var %current = $did(3).seltext
    var %comchan = $comchan(%current,0)
    var %i = 0
    while (%i < %comchan) {
      inc %i
      did -a $dname 4 $comchan(%current,%i)
    }
  }
}
alias -l _getComChans {
  ;Add,More,Exclusions,In,CSV,Format
  var %avoid = $me $+ ,ChanServ
  did -r _comchandlg 3
  var %chan = $1
  var %i = 0
  while (%i < $nick(%chan, 0)) {
    inc %i
    var %current = $nick(%chan, %i)
    if (!$istok(%avoid,%current,44)) && ($comchan(%current,0) > 1) {
      did -a _comchandlg 3 %current
    }
  }
}