revert BasePayment extension

src/pretix/plugins/paypal2/views.py

@@ -344,8 +344,6 @@ def webhook(request, *args, **kwargs):
     event_body = request.body.decode('utf-8').strip()
     event_json = json.loads(event_body)
 
-    return HttpResponse(status=500)
-
     # V1/V2 Sorting -- Start
     if 'event_type' not in event_json:
         return HttpResponse("Invalid body, no event_type given", status=400)

src/pretix/presale/views/order.py

@@ -352,7 +352,7 @@ class OrderDetails(EventViewMixin, OrderDetailMixin, CartMixin, TicketPageMixin,
                 if lp.state == OrderPayment.PAYMENT_STATE_PENDING and not pp.abort_pending_allowed:
                     ctx['can_pay'] = False
 
-            ctx['can_pay'] = ctx['can_pay'] and self.order._can_be_paid()
+            ctx['can_pay'] = ctx['can_pay'] and self.order._can_be_paid() is True
 
         elif self.order.status == Order.STATUS_PAID:
             ctx['can_pay'] = False