JSFiddle - React, Tailwind, and code Playground
HTML
<div id="tableDiv.PO.1">Div 1</div>
CSS
#tableDiv.PO.2 {height: 1em; width:1em; background:green;}
JavaScript
$("#tableDiv\\.PO\\." + 1).after('<div id="tableDiv.PO.' + 2 + '" style="display:none; display:table;">dfddfd</div>');