1 files changed, 5 insertions, 0 deletions
diff --git a/lib/PublicInbox/ExtMsg.pm b/lib/PublicInbox/ExtMsg.pm
index 0cba49dd..50680471 100644
--- a/lib/PublicInbox/ExtMsg.pm
+++ b/lib/PublicInbox/ExtMsg.pm
@@ -1,5 +1,10 @@
  # Copyright (C) 2015 all contributors <meta@public-inbox.org>
  # License: AGPLv3 or later (https://www.gnu.org/licenses/agpl-3.0.txt)
+#
+# Used by the web interface to link to messages outside of the our
+# public-inboxes.  Mail threads may cross projects/threads; so
+# we should ensure users can find more easily find them on other
+# sites.
  package PublicInbox::ExtMsg;
  use strict;
  use warnings;