Bug 1151290: It is possible to tell if someone made a private comment on a bug…

Bugzilla/Search.pm

@@ -2520,6 +2520,12 @@ sub _long_desc_changedby {
     push(@$joins, { table => 'longdescs', as => $table });
     my $user_id = $self->_get_user_id($value);
     $args->{term} = "$table.who = $user_id";
+
+    # If the user is not part of the insiders group, they cannot see
+    # private comments
+    if (!$self->_user->is_insider) {
+        $args->{term} .= " AND $table.isprivate = 0";
+    }
 }
 
 sub _long_desc_changedbefore_after {