Just tried this with TamperMonkey on Chrome: Tampermonkey - Chrome Web Store
// ==UserScript==
// @name PlayCanvsa JS Hint Update
// @namespace http://stevenyau.co.uk/
// @version 0.1
// @description Update JS Hint to latest
// @author Steven Yau
// @match https://playcanvas.com/editor/code/*
// @icon https://playcanvas.com/static-assets/images/icons/favicon.png
// @grant none
// ==/UserScript==
(function() {
(function(){var t=document.createElement("script");t.src="https://jshint.com/res/jshint/dist/jshint.js",t.onload=function(){var t;(t=editor.call("editor:codemirror")).setOption("lint",!1),t.setOption("lint",!0)},document.head.appendChild(t)})();
})();
Works like a charm