- Revert SORT=DISPLAY support, removed by mistake in r4160 (#1488327)

CHANGELOG

@@ -1,6 +1,7 @@
 CHANGELOG Roundcube Webmail
 ===========================
 
+- Revert SORT=DISPLAY support, removed by mistake (#1488327)
 - Fix autoselect_host() for login (#1488297)
 - Fix drafts update issues when edited from preview pane (#1488314)
 - Changed license to GNU GPLv3+ with exceptions for skins & plugins

program/include/rcube_imap_generic.php

@@ -1559,6 +1559,11 @@ class rcube_imap_generic
             return new rcube_result_index($mailbox);
         }
 
+        // RFC 5957: SORT=DISPLAY
+        if (($field == 'FROM' || $field == 'TO') && $this->getCapability('SORT=DISPLAY')) {
+            $field = 'DISPLAY' . $field;
+        }
+
         // message IDs
         if (!empty($add))
             $add = $this->compressMessageSet($add);