diff -r d1f9bea443f0 web/org.openbravo.retail.discounts.bytotal/js/ticketdiscountExtension.js
--- a/web/org.openbravo.retail.discounts.bytotal/js/ticketdiscountExtension.js	Tue Nov 07 17:52:31 2017 +0100
+++ b/web/org.openbravo.retail.discounts.bytotal/js/ticketdiscountExtension.js	Tue Dec 12 12:37:59 2017 +0100
@@ -15,7 +15,7 @@
       discountListOptionsDiscountChanged = DiscountsUIPrototype.discountChanged;
   var discountsContainer, comp, rule;
   DiscountsUIPrototype.discountChanged = _.wrap(DiscountsUIPrototype.discountChanged, function (wrapped) {
-    (_.bind(discountListOptionsDiscountChanged, this))();
+    (_.bind(discountListOptionsDiscountChanged, this))(arguments[1], arguments[2]);
     discountsContainer = this.$.discountsContainer;
     comp = this._searchSelectedComponent(this.$.discountsList.getValue());
     rule = OB.Model.Discounts.discountRules[comp.model.get('discountType')];