JSFiddle - React, Tailwind, and code Playground

HTML

<pre class="class1">random text</pre>
<pre class="class2">
    <span style="padding-right: 0.1px;">
        <span class="cm-operator">=</span>
		<span class="cm-operator interactive-linter-warning">===</span>
		<span class="cm-operator interactive-linter-warning interactive-linter-error">===</span>
    </span>
</pre>

JavaScript

$('pre').each(function(){
var val = $.trim($(this).text().replace(/\n+\s+/g,''));
   if( val == '======='){
alert($(this).attr('class'));    
}
});