Note: After saving, you have to bypass your browser's cache to see the changes. Google Chrome, Firefox, Microsoft Edge and Safari: Hold down the ⇧ Shift key and click the Reload toolbar button. For details and instructions about other browsers, see Wikipedia:Bypass your cache.
mw.loader.using(['mediawiki.util'],	function() {
	//document.title = "Update in progress...";
	//document.querySelector('h1').innerHTML = "h1 My new text!";
	//document.querySelector('div').innerHTML = "div My new text!";
	//document.querySelector('p').innerHTML = "p My new text!";
	//document.querySelector('span').innerHTML = "span My new text!";
	//$('h1').append(mw.config.get('wgRevisionId'));
	$("#mw_header h1, #content h1").append(mw.config.get('wgRevisionId'));
});