JSFiddle - React, Tailwind, and code Playground

JavaScript

window.onerror = function (e) {
    alert("unhandled error: " + e);
};

var p = new Promise(function (resolve, reject) {
    var nullObject = null;
    // Raise > TypeError: Cannot read property 'forceNullError' of null
    var x = nullObject.forceNullError(); 
    resolve();
});

p.then(function () { alert('success'); });