JSFiddle - React, Tailwind, and code Playground

HTML

<div id="container">
    <div class="example">Some Example text  
        <span id="eee"> text in the span </span>
    </div>
    <div class="example">Some more Example text</div>
</div>

JavaScript

$("#container").find(":not(iframe)").andSelf().contents().each(function() {
    if (this.nodeType == 3) {
        this.data = this.data.replace(/e/ig, "[X]");
    }
});