JSFiddle - React, Tailwind, and code Playground

HTML

<div class="ui-widget">
  <label for="tags">Tags:</label>
  <input id="tags" />
  <span id="tags-span"></span>
</div>

CSS

.ui-autocomplete {
  position: absolute;
  top: 100%;
  left: 0;
  z-index: 1000;
  float: left;
  display: none;
  min-width: 160px;
  _width: 160px;
  padding: 4px 0;
  margin: 2px 0 0 0;
  list-style: none;
  background-color: #ffffff;
  border-color: #ccc;
  border-color: rgba(0, 0, 0, 0.2);
  border-style: solid;
  border-width: 1px;
  -webkit-border-radius: 5px;
  -moz-border-radius: 5px;
  border-radius: 5px;
  -webkit-box-shadow: 0 5px 10px rgba(0, 0, 0, 0.2);
  -moz-box-shadow: 0 5px 10px rgba(0, 0, 0, 0.2);
  box-shadow: 0 5px 10px rgba(0, 0, 0, 0.2);
  -webkit-background-clip: padding-box;
  -moz-background-clip: padding;
  background-clip: padding-box;
  *border-right-width: 2px;
  *border-bottom-width: 2px;
  .ui-menu-item > a.ui-corner-all {
    display: block;
    padding: 3px 15px;
    clear: both;
    font-weight: normal;
    line-height: 18px;
    color: #555555;
    white-space: nowrap;
    &.ui-state-hover,
    &.ui-state-active {
      color: #ffffff;
      text-decoration: none;
      background-color: #0088cc;
      border-radius: 0px;
      -webkit-border-radius: 0px;
      -moz-border-radius: 0px;
      background-image: none;
    }
  }
}

JavaScript

var availableTags = [
  "ActionScript",
  "AppleScript",
  "Asp",
  "BASIC",
  "C",
  "C++",
  "Clojure",
  "COBOL",
  "ColdFusion",
  "Erlang",
  "Fortran",
  "Groovy",
  "Haskell",
  "Java",
  "JavaScript",
  "Lisp",
  "Perl",
  "PHP",
  "Python",
  "Ruby",
  "Scala",
  "Scheme"
];


$("#tags").autocomplete({
  source: availableTags,
  autoFocus: true,
  selectFirst: true,
  select: function(event, ui) {
    $("#tags").val(ui.item.value);
    $("#tags-span").text(ui.item.value);
  }
}).on('autocompletechange', function() {
  if ($(this).data('ui-autocomplete').selectedItem === null) {
  	//this will trigger your select automatically so it will handle other custom override you did for select
    $(this).data('ui-autocomplete').menu.element.children('li:first').children('a').trigger('click');
  }
});