Merge remote-tracking branch 'origin/MC-42968' into GL_PR_21102021

Author: glo71317

app/code/Magento/Paypal/view/frontend/web/js/in-context/button.js

@@ -22,7 +22,14 @@ define([
 
             this._super();
             this.renderPayPalButtons(element);
-            this.declinePayment = !customer().firstname && !cart().isGuestCheckoutAllowed;
+
+            if (cart().isGuestCheckoutAllowed === undefined) {
+                cart.subscribe(function (updatedCart) {
+                    this.declinePayment = !customer().firstname && !cart().isGuestCheckoutAllowed;
+
+                    return updatedCart;
+                }.bind(this));
+            }
 
             return this;
         },