[FIX] #921 Fixed issue when discard a modal with draggable element

web_dialog_size/__manifest__.py

@@ -15,7 +15,7 @@
               "Odoo Community Association (OCA)",
     'website': "http://acsone.eu",
     'category': 'web',
-    'version': '11.0.1.0.1',
+    'version': '11.0.1.0.2',
     'license': 'AGPL-3',
     'depends': [
         'web',

web_dialog_size/static/src/js/web_dialog_size.js

@@ -37,10 +37,12 @@ Dialog.include({
     },
 
     close: function() {
-        var draggable = this.$modal.draggable( "instance" );
+        if (this.$modal) {
+            var draggable = this.$modal.draggable("instance");
             if (draggable) {
                 this.$modal.draggable("destroy");
             }
+        }
         return this._super.apply(this, arguments);
     },