this is an example of the autocomplete jQuery ui ( JSON & Bold hightlighted)

Autocomplete JSON & Bold Hightlighted

$("#search-txt").autocomplete({

    source: function (req, responseFn) {
        $.ajax({
            url: "/search.json",
            dataType: "json",
            success: function(data) {
                
                var re = $.ui.autocomplete.escapeRegex(req.term);
                var matcher = new RegExp( "^" + re, "i" );
                var a = $.grep( data, function(item,index){
                    return matcher.test(item.value);
                });

                responseFn( a );

            },
            error: function (error) { 
                
            }
        });
    }
}).data('ui-autocomplete')._renderItem = function( ul, item) {
    var re = new RegExp("^" + this.term, "i") ;
    var t = item.value.replace(re,"<span style='font-weight:600;'>" + this.term + "</span>");
    return $( "<li></li>" )
        .data( "item.autocomplete", item )
        .append( "<a>" + t + "</a>" )
        .appendTo( ul );
};