Unfortunately there are no activation events for dialogs, but we can use something like this...
dialog x {
  size -1 -1 80 80
  title "text"
On *:dialog:x:init:0:.timerx 0 1 _isactive
On *:dialog:x:close:0:.timerx off
alias -l _isactive {
  if !$dialog(x).active {
    dialog -t x $iif($dialog(x).title == -,text!,-)

Paste this code in the remote and open the dialog - /dialog -md x x. Afterwards, minimize it and see what happens smile