Allow to disable ticket attachments to emails

src/pretix/base/services/mail.py

@@ -291,6 +291,8 @@ def mail_send_task(self, *args, to: List[str], subject: str, body: str, html: st
                     order = None
                 else:
                     with language(order.locale, event.settings.region):
+                        if not event.settings.mail_attach_tickets:
+                            attach_tickets = False
                         if position:
                             try:
                                 position = order.positions.get(pk=position)

src/pretix/base/settings.py

@@ -13,6 +13,7 @@ from django.core.validators import (
     MaxValueValidator, MinValueValidator, RegexValidator,
 )
 from django.db.models import Model
+from django.utils.text import format_lazy
 from django.utils.translation import (
     gettext_lazy as _, gettext_noop, pgettext, pgettext_lazy,
 )
@@ -1322,6 +1323,19 @@ DEFAULTS = {
         'default': 'classic',
         'type': str
     },
+    'mail_attach_tickets': {
+        'default': 'True',
+        'type': bool,
+        'form_class': forms.BooleanField,
+        'serializer_class': serializers.BooleanField,
+        'form_kwargs': dict(
+            label=_("Attach ticket files"),
+            help_text=format_lazy(
+                _("Tickets will never be attached if they're larger than {size} to avoid email delivery problems."),
+                size='4 MB'
+            ),
+        )
+    },
     'mail_attach_ical': {
         'default': 'False',
         'type': bool,