fix "Live search got stuck, on some chars"
fix "Live search got stuck, on some chars"

fix #1310, fix #1245

jesenko/bootstrap-select,wearespindle/select3,wearespindle/select3,anhtranqs3/bootstrap4-select,jesenko/bootstrap-select,anhtranqs3/bootstrap4-select,silviomoreto/bootstrap-select,silviomoreto/bootstrap-select