diff --git a/Documentation/RelNotes/1.7.8.4.txt b/Documentation/RelNotes/1.7.8.4.txt
index 3172f1cb3185c28a857096c9d1c51e82167e08fb..c21fc99bdb32622f619305d7945e0c3b1d66ab23 100644
--- a/Documentation/RelNotes/1.7.8.4.txt
+++ b/Documentation/RelNotes/1.7.8.4.txt
@@ -8,6 +8,11 @@ Fixes since v1.7.8.3
    directory when two paths in question are in adjacent directories and
    the name of the one directory is a prefix of the other.
 
+ * When producing a "thin pack" (primarily used in bundles and smart
+   HTTP transfers) out of a fully packed repository, we unnecessarily
+   avoided sending recent objects as a delta against objects we know
+   the other side has.
+
  * "git send-email" did not properly treat sendemail.multiedit as a
    boolean (e.g. setting it to "false" did not turn it off).