Fix allow_mail_archived_partner causing system notifications to send emails

allow_mail_archived_partner/models/mail_template.py

@@ -0,0 +1,27 @@
+import logging
+_logger = logging.getLogger(__name__)
+
+from odoo import models
+
+
+class MailTemplate(models.Model):
+    _inherit = "mail.template"
+
+    def generate_email(self, res_ids, fields=None):
+        """
+        Only allow archived partners when *explicitly* sending through a flow
+        that sets:
+            context['mail_notify_force'] = True
+
+        This prevents system notifications from inheriting your relaxed rules.
+        """
+        if self.model in ["sale.order", "account.move"] and self.env.context.get("mail_notify_force"):
+            return super(
+                MailTemplate,
+                self.with_context(
+                    active_test=False,
+                    include_archived_partners=True
+                )
+            ).generate_email(res_ids, fields)
+
+        return super().generate_email(res_ids, fields)