JSFiddle - React, Tailwind, and code Playground

HTML

<div id="container">
<button type="sumit" class="btn xs default" data-show="dialog">
    <i class="ellipsis-v">x</i>
    <span>fooo</span>
</button>
<button type="sumit" class="btn xs default" data-show="dialog">
    <i class="ellipsis-v">x</i>
    <span>fooo</span>
</button>
</div>

CSS

.ellipsis-v{
background-color:green;    
    width:10px;
    height:10px;
}
span{
  background-color:yellow;    
}

JavaScript

function handler(e){
 var t=e.target;
 if(t.dataset['show']=='dialog'||t.parentNode.dataset['show']=='dialog'){
  console.log(e.target);
  alert(e.target.nodeName+' clicked');
 }
}
document.getElementById('container').addEventListener('click',handler,false);