Add debug trace when the clipboard changes
diff --git a/unix/xserver/hw/vnc/vncSelection.c b/unix/xserver/hw/vnc/vncSelection.c
index 02a1cd1..51dfd9c 100644
--- a/unix/xserver/hw/vnc/vncSelection.c
+++ b/unix/xserver/hw/vnc/vncSelection.c
@@ -509,6 +509,9 @@
   if (info->client == serverClient)
     return;
 
+  LOG_DEBUG("Selection owner change for %s",
+            NameForAtom(info->selection->selection));
+
   if ((info->selection->selection != xaPRIMARY) &&
       (info->selection->selection != xaCLIPBOARD))
     return;