fix bug #10783 copy sender in the Inbox.

docs/changelog/7.x.x.txt

@@ -1,4 +1,5 @@
 7.7.18
+ - fixed #10783: Inbox Copy Sender broken
  - fixed #10782: Send Message friend_wholeName template var
  - fixed #10778: Matrix navigation: list attributes
  - fixed #10776: i18n AuthLDAP::7 description 

lib/WebGUI/Account/Inbox.pm

@@ -1334,9 +1334,9 @@ sub www_sendMessageSave {
 
     foreach my $uid (@toUsers) {
         $messageProperties->{userId} = $uid;
-        $inbox->addMessage($messageProperties);
+        my $thisMessage = $inbox->addMessage($messageProperties);
         if ($uid eq $session->user->userId) {
-            $message->setRead;
+            $thisMessage->setRead;
         }
     }