JSFiddle - React, Tailwind, and code Playground

HTML

<link rel="stylesheet" href="http://ajax.googleapis.com/ajax/libs/jqueryui/1.8/themes/cupertino/jquery-ui.css">
<ul id='firstOne'>First
    <li class='listItem'>oneF</li>
    <li class='listItem'>twoF</li>
</ul>
<ul id='secondOne'>Second<span></span>
    <li class='listItem'>oneS</li>
    <li class='listItem'>twoS</li>
</ul>

CSS

ul{border:solid 1px red;margin:10px;}
li{border:solid  1px blue;}

JavaScript

$('#firstOne .listItem').draggable({
    helper: 'clone'
});
giveId($('#secondOne'));

$("#secondOne").droppable({
    activeClass: "ui-state-default",
    hoverClass: "ui-state-hover",
    drop: function(event, ui) {
        $(ui.draggable).clone().css('background-color', 'pink').attr('id', 'content-' + ($(this).find('.listItem').length + 1)).appendTo(this).siblings().css('background-color', 'yellow');
        showId($(event.target));
    },
    accept: '#firstOne .listItem'
}).sortable({
    revert: true,
    update: function(event, ui) {
        showId($(event.target));
    },
    receive: function(event, ui) {
        alert('receipt');
    }
});

function giveId(list) {
    list.find(".listItem").each(function(index) {
        $(this).attr("id", "content-" + index);
    });
    showId(list)
}

function showId(list) {
    list.find('span').text(list.find('.listItem:last').attr('id'));
}