- Проверяем другую библиотеку jquery

common/modules/school/assets/WidgetAssetBundle.php

@@ -20,6 +20,7 @@ class WidgetAssetBundle extends AssetBundle
         'css/style_add.css',
 	];
 	public $js = [
+		'js/jquery.js',
 		'js/school.js',
         'js/jquery.form.js',
 	];

common/modules/school/assets/js/school.js

@@ -150,11 +150,6 @@ $(document).ready(function() {
         type: 'inline',
         preloader: false
     });
-
-    $('.mfp-close').on('click', function() {
-        alert('asd');
-        $('.mfp-wrap').click();
-    });
 }); 
  
 // pre-submit callback