JSFiddle - React, Tailwind, and code Playground

HTML

<input type="checkbox" id="test">

JavaScript

var testInput = document.querySelector("#test");

var MO = (window.MutationObserver || window.WebKitMutationObserver || window.MozMutationObserver);
var observer = new MO(function(){ console.log("disabled changed") });
observer.observe(testInput, { attributes: true, attributeFilter: ["disabled"] });

testInput.setAttribute("disabled", "disabled");