JSFiddle - React, Tailwind, and code Playground

HTML

<table id="first_table">
<tr><td>some content 1</td><td>some content 2</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').attr("tabindex", "0").on("mouseenter focus", function() {
  var jq = $(this);
  var cell_text = jq.text(),
      offset = jq.offset();

  $('.banner').css({
    top: offset.top,
    left: offset.left
  }).text('Значение в ячейке: ' + cell_text).stop(true).fadeIn(300);
}).on("mouseleave blur", function() {
  $('.banner').stop(true).fadeOut(300);
});