JSFiddle - React, Tailwind, and code Playground

HTML

<div class="popular-tags">
  <span class="left">Popular: </span>
  <br><br>
  <div class="tag-container">    
    <button id="tagBtn" class="btn normal tag" style="padding-left:10px; padding-right: 5px; border-radius: 4px; position: relative; margin-right: 20px;">
      <span style="float: left; font-weight: normal;">Popular Tag</span>
      <span class="growth-percentage" style="float: right; margin-left: 5px;">67%</span>
   </button>
     <button id="tagBtn" class="btn normal tag" style="padding-left:10px; padding-right: 5px; border-radius: 4px; position: relative; margin-right: 20px;">
      <span style="float: left; font-weight: normal;">Another</span>
      <span class="growth-percentage" style="float: right; margin-left: 5px;">2%</span>
   </button>
  </div>
</div>

JavaScript

var $tag = $('.popular-tags').find('.tag');
$tag.click(function(){
  var $this = $(this);
  var text = $this.text();
  var lo = text.replace(/[^A-Za-z]/g, '');
  alert(lo)
});