JSFiddle - React, Tailwind, and code Playground

HTML

<script src="//code.jquery.com/jquery-1.10.2.min.js"></script>
<script src="//code.jquery.com/ui/1.10.4/jquery-ui.js"></script>
<link rel="stylesheet" href="//code.jquery.com/ui/1.10.4/themes/smoothness/jquery-ui.css">
<body>
<div class="demo">
<div class="ui-widget">
<form action="" method="GET">
    <label>Search for a designation: </label>
    <select id="combobox" name="designation">
        <option value=""></option>
            <option value="1">Test 1a</option>
            <option value="2">Test 2b</option>
            <option value="3">Test 3c</option>
        <optgroup label="Category 1">
            <option value="1">Test 1</option>
            <option value="2">Test 2</option>
            <option value="3">Test 3</option>
        </optgroup>
        <optgroup label="Category 2">
            <option value="a">Test a</option>
            <option value="b">Test b</option>
            <option value="c">Test c</option>
        </optgroup>
    </select><br/>
    <input type="submit" name="Submit" value="submit">
    </form>
<div id="test" style="display: none;"><ul class="ui-autocomplete ui-menu ui-widget ui-widget-content ui-corner-all" role="listbox" aria-activedescendant="ui-active-menuitem" style="z-index: 1; top: 43px; left: 238.283px; display: block; width: 577px;"><li class="ui-menu-item" role="menuitem"><a class="ui-corner-all" tabindex="-1">No Matches</a></li></ul></div>
</div>
</div><!-- End demo -->
</body>

CSS

<style>
.ui-combobox {
        position: relative;
        display: inline-block;
    }
    .ui-combobox-toggle {
        position: absolute;
        top: 0;
        bottom: 0;
        margin-left: -1px;
        padding: 0;
        /* adjust styles for IE 6/7 */
        *height: 1.7em;
        *top: 0.1em;
    }
    .ui-combobox-input {
        margin: 0;
        padding: 0.3em;
    }
    #test{
    margin-left:240px;    
    }
</style>

JavaScript

(function($) {
    $.widget("ui.combobox", {
        _create: function() {
            var input, self = this,
                select = this.element.hide(),
                selected = select.children(":selected"),
                value = selected.val() ? selected.text() : "",
                wrapper = this.wrapper = $("<span>").addClass("ui-combobox").insertAfter(select);

            input = $("<input>").appendTo(wrapper).val(value).addClass("ui-state-default ui-combobox-input").autocomplete({
                delay: 0,
                minLength: 0,
                source: function(request, response) {
                    var matcher = new RegExp($.ui.autocomplete.escapeRegex(request.term), "i");

                    response(select.find("option").map(function() {
                        var text = $(this).text();
                        if (this.value && (!request.term || matcher.test(text))) return {
                            label: text.replace(
                            new RegExp("(?![^&;]+;)(?!<[^<>]*)(" + $.ui.autocomplete.escapeRegex(request.term) + ")(?![^<>]*>)(?![^&;]+;)", "gi"), "<strong>$1</strong>"),
                            value: text,
                            option: this,
                            category: $(this).closest("optgroup").attr("label")
                        };
                        //MK 
                        $('#test').attr('style', 'display: none;');
                    }).get());
                },
                select: function(event, ui) {
                    ui.item.option.selected = true;
                    self._trigger("selected", event, {
                        item: ui.item.option
                    });
                },
                change: function(event, ui) {
                    if (!ui.item) {
                        var matcher = new RegExp("^" + $.ui.autocomplete.escapeRegex($(this).val()) + "$", "i"),
                            valid = false;
                       ...