diff --git a/addons/mail/models/mail_message.py b/addons/mail/models/mail_message.py
index 1339f9fe5c9..1ced8572620 100644
--- a/addons/mail/models/mail_message.py
+++ b/addons/mail/models/mail_message.py
@@ -888,7 +888,7 @@ class Message(models.Model):
             else:
                 record_name = False
                 default_subject = False
-            reactions_per_content = defaultdict(lambda: self.env['mail.message.reaction'])
+            reactions_per_content = defaultdict(self.env['mail.message.reaction'].sudo().browse)
             for reaction in message_sudo.reaction_ids:
                 reactions_per_content[reaction.content] |= reaction
             reaction_groups = [{