Fatal error: Uncaught Error: Class "Horde_Mail_Rfc822" not found in /home/tzuovhm/tzuovhm/apps_/mail/vendor/bytestream/horde-listheaders/lib/Horde/ListHeaders.php:22 Stack trace: #0 {main} thrown in /home/tzuovhm/tzuovhm/apps_/mail/vendor/bytestream/horde-listheaders/lib/Horde/ListHeaders.php on line 22