myaac/system/templates/tinymce.html.twig

<script type="text/javascript" src="{{ constant('BASE_URL') }}tools/js/tinymce/tinymce.min.js"></script>
<script type="text/javascript">
	let unsaved = false;
	let lastContent = '';

	function tinymceInit() {
		tinymce.init({
			selector: "#editor",
			theme: "silver",
			plugins: 'preview searchreplace autolink directionality visualblocks visualchars fullscreen image link media template codesample table charmap pagebreak nonbreaking anchor insertdatetime advlist lists wordcount help code emoticons',
			toolbar1: 'formatselect | bold italic strikethrough forecolor backcolor | emoticons link | alignleft aligncenter alignright alignjustify  | numlist bullist outdent indent  | removeformat code',
			resize: 'both',
			image_advtab: true,
			images_upload_url: '{{ constant('ADMIN_URL') }}tools/upload_image.php',
			images_upload_credentials: true,

			relative_urls: true,
			document_base_url: "{{ constant('BASE_URL') }}",

			setup: function (ed) {
				ed.on('NodeChange', function (e) {
					if (ed.getContent() !== lastContent) {
						unsaved = true;
					}
				});
			}
		});
	}

	$(document).ready(function () {
		$(":input").change(function () { //triggers change in all input fields including text type
			unsaved = true;
		});

		$("#form").submit(function (event) {
			unsaved = false;
		});

		lastContent = $("#editor").val();
	});

	function unloadPage() {
		if (unsaved) {
			return "You have unsaved changes on this page. Do you want to leave this page and discard your changes or stay on this page?";
		}
	}

	window.onbeforeunload = unloadPage;
</script>