JSFiddle - React, Tailwind, and code Playground

HTML

<table id="first_table">
<tr><td>some content</td></tr>
</table>
<div class="banner"></div>

CSS

.banner{
  position:absolute;
  width:200px;
  z-index:1;
  background:#000;
  padding:20px;
  color:#FFF;
  font-size:14px;
  display:none;
  margin-top:25px;
}

JavaScript

$('td').mouseenter(function() {
    const $this = $(this);
    var cell_text = $this.text(),
        offset = $this.offset();


    $('.banner').css({
        'top': offset.top,
        'left': offset.left
    }).text('Значение в ячейки' + cell_text).stop(true).fadeIn(300);
});

$('#first_table').mouseleave(function() {
    $('.banner').stop(true).fadeOut(300);
});