diff --git a/addons/mail/controllers/thread.py b/addons/mail/controllers/thread.py
index 5224f9f3527..70a43ede19a 100644
--- a/addons/mail/controllers/thread.py
+++ b/addons/mail/controllers/thread.py
@@ -94,6 +94,7 @@ class ThreadController(http.Controller):
                 'ids': canned_response_ids,
             })
         thread = request.env[thread_model].with_context(active_test=False).search([("id", "=", thread_id)])
+        thread = thread.with_context(active_test=True)
         if not thread:
             raise NotFound()
         if "body" in post_data: