JSFiddle - React, Tailwind, and code Playground

HTML

<div class="PanelTabs stream-field" role="tablist">
  <div class="panel-heading button-group">
<ul class="nav nav-tabs button-group col8">
<li role="presentation" class="button button-small button-secondary active"><a href="#49600-0-en" aria-controls="49600-0-en" role="tab" data-toggle="tab">Inglés</a></li>
<li role="presentation" class="button button-small button-secondary"><a href="#49600-1-ca" aria-controls="49600-1-ca" role="tab" data-toggle="tab">Catalán</a></li>
<li role="presentation" class="button button-small button-secondary"><a href="#49600-2-es" aria-controls="49600-2-es" role="tab" data-toggle="tab">Español</a></li>
</ul>
</div>
  <div class="panel-heading button-group">
<ul class="nav nav-tabs button-group col8">
<li role="presentation" class="button button-small button-secondary active"><a href="#49600-0-en" aria-controls="49600-0-en" role="tab" data-toggle="tab">Inglés</a></li>
<li role="presentation" class="button button-small button-secondary"><a href="#49600-1-ca" aria-controls="49600-1-ca" role="tab" data-toggle="tab">Catalán</a></li>
<li role="presentation" class="button button-small button-secondary"><a href="#49600-2-es" aria-controls="49600-2-es" role="tab" data-toggle="tab">Español</a></li>
</ul>
</div>
  <div class="panel-heading button-group">
<ul class="nav nav-tabs button-group col8">
<li role="presentation" class="button button-small button-secondary active"><a href="#49600-0-en" aria-controls="49600-0-en" role="tab" data-toggle="tab">Inglés</a></li>
<li role="presentation" class="button button-small button-secondary"><a href="#49600-1-ca" aria-controls="49600-1-ca" role="tab" data-toggle="tab">Catalán</a></li>
<li role="presentation" class="button button-small button-secondary"><a href="#49600-2-es" aria-controls="49600-2-es" role="tab" data-toggle="tab">Español</a></li>
</ul>
</div>
</div>

CSS

.button-group {
    border: 1px solid black;
}

JavaScript

/* Creates the copy buttons in the header of each stream field */
$(function () {
	/* Iterate all stream fields, put the copy buttons in each one.*/
	$('div.PanelTabs.stream-field').each(function () {
		var header = $(this).children('div.panel-heading:last');
		header.prepend('hola');
		});
});