Focusout has stopped working

Is this a bug?
#1

With a select box in the ACF Wordpress environment, I had this javascript code which used to work fine.

$('#s2id_acf-field_598c36750d67e-input').focusout(function () {
   newValue = $('#s2id_acf-field_598c36750d67e-input').select2("val");
   // did some stuff with new value
   console.log ( "new value = " + newValue );
});

And it worked fine. Now it’s simply not firing and we never even get to the console.log.

Has there been a change somewhere?