JSFiddle - React, Tailwind, and code Playground

HTML

<input type="button" value="Click me" onclick="throw_msg()">
<div id="error-box"></div>

CSS

#error-box {
    height: 30px;
    line-height: 30px;
    background: #c00;
    text-align: center;
    color: #fff;
    font-weight: bold;
    position: absolute;
    bottom: 0;
    width: 100%;
}

JavaScript

function throw_msg() {
    try {
        var a = '';
        alert(b);
    }
    catch(throw_error) {
        document.getElementById('error-box').innerHTML=throw_error.message;
        setTimeout(
            function() {
                document.getElementById('error-box').innerHTML='';
            }, 2000);
    }
}