diff --git a/src/applications/calendar/editor/PhabricatorCalendarEventEditor.php b/src/applications/calendar/editor/PhabricatorCalendarEventEditor.php
--- a/src/applications/calendar/editor/PhabricatorCalendarEventEditor.php
+++ b/src/applications/calendar/editor/PhabricatorCalendarEventEditor.php
@@ -370,9 +370,7 @@
   protected function shouldSendMail(
     PhabricatorLiskDAO $object,
     array $xactions) {
-
-    $xactions = mfilter($xactions, 'shouldHide', true);
-    return $xactions;
+    return true;
   }
 
   protected function getMailSubjectPrefix() {