JSFiddle - React, Tailwind, and code Playground

HTML

<label for="search">Search: </label>
    <input id="search" />

CSS

.ui-autocomplete-category {
        font-weight: bold;
        padding: .2em .4em;
        margin: .8em 0 .2em;
        line-height: 1.5;
    }

JavaScript

$.widget( "custom.catcomplete", $.ui.autocomplete, {
  
        _renderMenu: function( ul, items ) {
            var self = this,
                currentCategory = "";
            $.each( items, function( index, item ) {
                if ( item.category != currentCategory ) {
                    ul.append( "<li class='ui-autocomplete-category'>" + item.category + "</li>" );
                    currentCategory = item.category;
                }
                self._renderItem( ul, item );
            });
        }

    });

$(function() {
        var data = [{"category":"\u0410\u043b\u0442\u0430\u0439\u0441\u043a\u0438\u0439 \u043a\u0440\u0430\u0439","label":"\u0411\u0430\u0440\u043d\u0430\u0443\u043b"},{"category":"\u0410\u043b\u0442\u0430\u0439\u0441\u043a\u0438\u0439 \u043a\u0440\u0430\u0439","label":"\u043f\u043e\u0441. \u041d\u043e\u0432\u043e\u0430\u043b\u0442\u0430\u0439\u0441\u043a"},{"category":"\u0410\u043b\u0442\u0430\u0439\u0441\u043a\u0438\u0439 \u043a\u0440\u0430\u0439","label":"\u0411\u0438\u0439\u0441\u043a"},{"category":"\u0410\u0440\u0445\u0430\u043d\u0433\u0435\u043b\u044c\u0441\u043a\u0430\u044f \u043e\u0431\u043b\u0430\u0441\u0442\u044c","label":"\u0410\u0440\u0445\u0430\u043d\u0433\u0435\u043b\u044c\u0441\u043a"},{"category":"\u0410\u0440\u0445\u0430\u043d\u0433\u0435\u043b\u044c\u0441\u043a\u0430\u044f \u043e\u0431\u043b\u0430\u0441\u0442\u044c","label":"\u0421\u0435\u0432\u0435\u0440\u043e\u0434\u0432\u0438\u043d\u0441\u043a"},{"category":"\u0410\u0441\u0442\u0440\u0430\u0445\u0430\u043d\u0441\u043a\u0430\u044f \u043e\u0431\u043b\u0430\u0441\u0442\u044c","label":"\u0410\u0441\u0442\u0440\u0430\u0445\u0430\u043d\u044c"},{"category":"\u0411\u0435\u043b\u0433\u043e\u0440\u043e\u0434\u0441\u043a\u0430\u044f \u043e\u0431\u043b\u0430\u0441\u0442\u044c","label":"\u0411\u0435\u043b\u0433\u043e\u0440\u043e\u0434"},{"category":"\u0412\u043e\u043b\u0433\u043e\u0433\u0440\u0430\u0434\u0441\u043a\u0430\u044f...