JSFiddle - React, Tailwind, and code Playground

HTML

<div id="message" contenteditable="true">Digite sua mensagem</div>

JavaScript

$(function() {

    var $target = $('#message');
    
    $target.on("keyup", function() {

        var value = $target.text();

        if (value.length === 0 || !value.trim())
            alert(value);

        // continue...
        return false;
    });
});