Customer accounts: Only link orders by email if wanted

src/pretix/control/forms/organizer.py

@@ -285,6 +285,7 @@ class OrganizerSettingsForm(SettingsForm):
     )
     auto_fields = [
         'customer_accounts',
+        'customer_accounts_link_by_email',
         'contact_mail',
         'imprint_url',
         'organizer_info_text',

src/pretix/control/templates/pretixcontrol/organizers/edit.html

@@ -55,6 +55,7 @@
                     <fieldset>
                         <legend>{% trans "Customer accounts" %}</legend>
                         {% bootstrap_field sform.customer_accounts layout="control" %}
+                        {% bootstrap_field sform.customer_accounts_link_by_email layout="control" %}
                         {% bootstrap_field sform.name_scheme layout="control" %}
                         {% bootstrap_field sform.name_scheme_titles layout="control" %}
                     </fieldset>

src/pretix/control/views/organizer.py

@@ -1747,9 +1747,12 @@ class CustomerDetailView(OrganizerDetailViewMixin, OrganizerPermissionRequiredMi
     context_object_name = 'orders'
 
     def get_queryset(self):
+        q = Q(customer=self.customer)
+        if self.request.organizer.settings.customer_accounts_link_by_email:
+            # This is safe because we only let customers with verified emails log in
+            q |= Q(email__iexact=self.customer.email)
         qs = Order.objects.filter(
-            Q(customer=self.customer)
-            | Q(email__iexact=self.customer.email)
+            q
         ).select_related('event').order_by('-datetime')
         return qs