i found a solution , hopes implement on future release;
the situation is when using bootstrap modal, and shows chosen item, if press esc key, both modal and chosen close,,, expected only chosen hide, and modal stills i modifed
i use stoppropagation.
the calls con keyup_checker and keydown_checker and put this lines:
[keydown_checker]
case 27:
if (this.results_showing) {
evt.stopPropagation();
this.results_hide();
}
return true;

[keyup_checker]
case:27
if (this.results_showing) {
evt.stopPropagation();
this.results_hide();
}
return true;