Index: src/applications/differential/constants/DifferentialAction.php
===================================================================
--- src/applications/differential/constants/DifferentialAction.php
+++ src/applications/differential/constants/DifferentialAction.php
@@ -122,6 +122,7 @@
       self::ACTION_ADDCCS         => 'added CCs to',
       self::ACTION_CLAIM          => 'commandeered',
       self::ACTION_REOPEN         => 'reopened',
+      DifferentialTransaction::TYPE_INLINE => 'commented on',
     );
 
     if (!empty($verbs[$action])) {
Index: src/applications/differential/mail/DifferentialCommentMail.php
===================================================================
--- src/applications/differential/mail/DifferentialCommentMail.php
+++ src/applications/differential/mail/DifferentialCommentMail.php
@@ -154,6 +154,10 @@
     $body[] = null;
 
     foreach ($this->getComments() as $comment) {
+      if ($comment->getAction() == DifferentialTransaction::TYPE_INLINE) {
+        // These have comment content now, but are rendered below.
+        continue;
+      }
       $content = $comment->getContent();
       if (strlen($content)) {
         $body[] = $this->formatText($content);