Merge remote-tracking branch 'origin/MAGETWO-93963' into 2.3-develop

Author: serhii-balko

app/code/Magento/Checkout/view/frontend/web/js/sidebar.js

@@ -61,20 +61,23 @@ define([
             };
             events['click ' + this.options.button.checkout] = $.proxy(function () {
                 var cart = customerData.get('cart'),
-                    customer = customerData.get('customer');
+                    customer = customerData.get('customer'),
+                    element = $(this.options.button.checkout);
 
                 if (!customer().firstname && cart().isGuestCheckoutAllowed === false) {
                     // set URL for redirect on successful login/registration. It's postprocessed on backend.
                     $.cookie('login_redirect', this.options.url.checkout);
 
                     if (this.options.url.isRedirectRequired) {
+                        element.prop('disabled', true);
                         location.href = this.options.url.loginUrl;
                     } else {
                         authenticationPopup.showModal();
                     }
 
                     return false;
                 }
+                element.prop('disabled', true);
                 location.href = this.options.url.checkout;
             }, this);