In Zabbix 3.0 and 3.4, this line of code is not needed in frontends/php/app/controllers/CControllerAcknowledgeEdit.php:

order_result($data['acknowledges'], 'clock', ZBX_SORT_DOWN);

In Zabbix 3.4 this code block should be moved outside loop in frontends/php/include/events.inc.php L335-L337:

if ($config['event_ack_enable']) {
	$acknowledges = makeEventsAcknowledges($events, $backurl);
}

Patch files added.