JSFiddle - React, Tailwind, and code Playground

HTML

<button>Click me</button>

JavaScript

CS = {};
window.foo = 'global';
CS.OverviewController = {
    foo: "bar",
    
    render: function() {
        console.log("Rendering. foo = " + this.foo);
    }    
};

CS.handleClick = function(callback) {
    console.log("handleClick");
    if (callback) {
        callback();
    }
};

window.foo = 'global';
$("button").click(function(e) {
    CS.handleClick(CS.OverviewController.render);
});