JSFiddle - React, Tailwind, and code Playground

HTML

<div id="comment">
    <textarea rows="3" cols="20"></textarea>
    <a class="overlay" href="" style="display: none; position: absolute;">You must login</a>
</div>

JavaScript

$('#comment').mouseenter(function() {
    var textarea = $(this).find('textarea'); 
    var overlay = $(this).find('.overlay');

    var pos = textarea.position();
    overlay.css({
        top: pos.top,
        left: pos.left,
        width: textarea.width(),
        height: textarea.height(),
        display: 'block'
    });
});

$('#comment').mouseleave(function() {
    var overlay = $(this).find('.overlay');
    overlay.css({
        display: 'none'
    });
});