JSFiddle - React, Tailwind, and code Playground

HTML

<textarea class="textAreaMultiline" 
          placeholder="Hello, \nThis is multiline example \n\nHave Fun"
          rows="5" cols="35"></textarea>

JavaScript

var textAreas = document.getElementsByTagName('textarea');

Array.prototype.forEach.call(textAreas, function(elem) {
    elem.placeholder = elem.placeholder.replace(/\\n/g, '\n');
});