JSFiddle - React, Tailwind, and code Playground

HTML

<div id="container"></div>

JavaScript

$(function () {
    var MyClass = function () {};
    MyClass.prototype = {
        show: function () {
            console.log('OK');
        }
    };

    $.widget('ui.myWidget', {
        MY_SINGLETON: new MyClass(),
        show: function () {
            //console.log('show', this.MY_SINGLETON.show, (new MyClass()).show);
            this.MY_SINGLETON.show();
        }
    });

    $('#container').myWidget();
    $('#container').myWidget('show');
});