JSFiddle - React, Tailwind, and code Playground

HTML

<span class="output"></span>

JavaScript

var SeralCore = SeralCore || function () {
        this.initSeral();
        return this;
    };

window.onload = function () {
    this.SeralCore = new SeralCore();
};

SeralCore.prototype = {

    page: 'Page',
    
    initSeral: function ()
    {
        this.registerPage.start();
    },
    
    registerPage: {
        start: function ()
        {
            alert(SeralCore.page);
        }
    }
};