JSFiddle - React, Tailwind, and code Playground

HTML

<form>
    <div>
        
    </div>
</form>

CSS

body {
    font-family: Verdana, Arial, sans-serif;
    font-size: 12px;
}

JavaScript

Foo = function() {
    this.foo = "foo";
};

Foo.prototype.Em = function() {
    alert(this.foo);
};

var _ = new Foo();

// Calls 'Em()' in the context of '_':
_.Em();

// Calls 'Em()' in the context of 'window':
(0, _.Em)();