JSFiddle - React, Tailwind, and code Playground

HTML

<link rel="stylesheet" href="http://ajax.googleapis.com/ajax/libs/jqueryui/1.8.4/themes/ui-lightness/jquery-ui.css">
<img src = "http://dummyimage.com/120x90/f00/fff.png&text=my+image" />

JavaScript

var Box = function() {
    // the constructor
};
Box.prototype.setTitle = function( new_title ) {
    this.title = new_title;
    this.applyTitle();
};
Box.prototype.applyTitle = function() {
    document.body.innerHTML = this.title;
};

var mywindow = new Box();
mywindow.setTitle( "this is the title" );