for use with Gravity Forms to set options for enhanced ui drop downs, add to theme's functions.php file

gform_chosen_options

// set options for chosen e.g disable search or set width to use percentage
add_action('gform_pre_render','set_chosen_options');
function set_chosen_options($form){
    if(wp_script_is('gforms_chosen',$list='queue')){
?>
<script>
  gform.addFilter('gform_chosen_options','set_chosen_options_js');
	function set_chosen_options_js(options,element){
		//options.placeholder_text_single = 'Selectionner une Option'; // set default placeholder for blank first option
		//options.search_contains = true; // search options for partial matches
		options.max_selected_options = 2; // limit how many options may be chosen in a multi-select
		
		/* options available for use once chosen is updated to 0.9.14 or newer */
		//options.disable_search_threshold = 5; // disable search if select has less than 5 options
		//options.disable_search = true; // disable search altogether
		//options.width = '100%'; // set chosen to use percentage based width
		//options.allow_single_deselect = true; // add a UI element to single select box for option deselection, will only work if the first option has blank text
		
		return options;
	}
</script>
<?php
        }
	return $form;
}