JSFiddle - React, Tailwind, and code Playground

HTML

<html>
<head>
<title>JQuery.extend Test</title>
</head>
<body bgcolor="#000000" onload='runTest();'>
<div id='console' style='color:#FFFFFF;'></div>
</body>
</html>

JavaScript

function SimpleObject(test_scalar){
    this.t_scalar = test_scalar;
    this.ToString = function(){
        return "S: " + this.t_scalar;
    }
}

function TestObject(test_scalar,test_array,test_object){
    this.t_scalar = test_scalar;
    this.t_object = test_object;
    this.ToString = function(){
        return "S: " + this.t_scalar + ", O: {" + this.t_object.ToString() + "}";
    }
}

function Console(id){
    this.console = document.getElementById(id);
    this.write = function(str,color){
        if(str!=undefined){
            var textElement = this.console.appendChild(document.createElement('text'));
            textElement.appendChild(document.createTextNode(str));
            if(color!=undefined)
                textElement.setAttribute('style','color:'+color+';');
        }
    }
    this.writeline = function(str,color){
        if(str!=undefined){
            var textElement = this.console.appendChild(document.createElement('text'));
            textElement.appendChild(document.createTextNode(str));
            if(color!=undefined)
                textElement.setAttribute('style','color:'+color+';');
        }
        this.console.appendChild(document.createElement('br'));
    }
}

function runTest(){
    var out = new Console('console');
    
    var t0 = new TestObject(3.14,new Array(3,1,4,1,5,9,2),new TestObject(1.61,new Array(1,6,1,8,0,3,3),new SimpleObject(2)));
    
    out.writeline("Original Values");
    out.writeline("t0 - " + t0.ToString()+";");
    out.writeline();
    
    t0.t_scalar = 1; //works fine!
    out.write("Level 1 Change - ");
    out.writeline("Expected","#44FF44");
    out.writeline("t0 - " + t0.ToString()+";");
    out.writeline();
    
    t0.t_object.t_scalar = 23; //works fine!
    out.write("Level 2 Change - ");
    out.writeline("Expected","#44FF44");
    out.writeline("t0 - " + t0.ToString()+";");
    out.writeline();
    
    t0.t_object.t_object.t_scalar = 42; //works fine!
    out.write("Level 3 Change - ");
   ...