--- a/program/lib/Roundcube/rcube_imap.php	Thu Jan 18 07:47:04 2018 -0500
+++ b/program/lib/Roundcube/rcube_imap.php	Thu Aug 30 16:15:17 2018 -0400
@@ -814,6 +814,7 @@
      */
     protected function _list_messages($folder='', $page=NULL, $sort_field=NULL, $sort_order=NULL, $slice=0)
     {
+      	#rcube::write_log('mail',"_lm |$folder| $sort_field ".$this->threading);
         if (!strlen($folder)) {
             return array();
         }
@@ -1398,6 +1399,7 @@
             }
         }
 
+	#rcube::write_log('mail','cache? '.$this->get_mcache_engine());
         // check local cache
         if ($mcache = $this->get_mcache_engine()) {
             return $mcache->get_index($folder, $this->sort_field, $this->sort_order);
@@ -1456,7 +1458,7 @@
                 if ($search) {
                     $query = trim($query . ' UID ' . $search);
                 }
-
+		#rcube::write_log('mail',"abouttosort $sort_field $query");
                 $index = $this->conn->sort($folder, $sort_field, $query, true);
             }
 
@@ -1512,10 +1514,10 @@
      */
     protected function sort_threads($threads)
     {
+      #rcube::write_log('mail','sort_threads '.count($threads)." ".$this->sort_field);
         if ($threads->is_empty()) {
             return;
         }
-
         // THREAD=ORDEREDSUBJECT: sorting by sent date of root message
         // THREAD=REFERENCES:     sorting by sent date of root message
         // THREAD=REFS:           sorting by the most recent date in each thread
@@ -1523,7 +1525,7 @@
         if ($this->threading != 'REFS' || ($this->sort_field && $this->sort_field != 'date')) {
             $sortby = $this->sort_field ? $this->sort_field : 'date';
             $index  = $this->index($this->folder, $sortby, $this->sort_order, true, true);
-
+	    #rcube::write_log('mail',"sort_threads $sortby".print_r($index,true));
             if (!$index->is_empty()) {
                 $threads->sort($index);
             }