From 986944c2613db61f1444b9ba2405a187d411ee65 Mon Sep 17 00:00:00 2001
From: Ralf Becker <RalfBecker@outdoor-training.de>
Date: Tue, 9 Nov 2021 08:39:21 +0100
Subject: [PATCH] fix PHP 8.0 TypeError: Unsupported operand types:
 EGroupware\Api\DateTime - EGroupware\Api\DateTime

---
 calendar/inc/class.calendar_boupdate.inc.php | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/calendar/inc/class.calendar_boupdate.inc.php b/calendar/inc/class.calendar_boupdate.inc.php
index fde5445c5d..849d1bcd50 100644
--- a/calendar/inc/class.calendar_boupdate.inc.php
+++ b/calendar/inc/class.calendar_boupdate.inc.php
@@ -375,7 +375,7 @@ class calendar_boupdate extends calendar_bo
 		}
 		$checked = 0;
 		$start = microtime(true);
-		$duration = $event['end']-$event['start'];
+		$duration = Api\DateTime::to($event['end'], 'ts') - Api\DateTime::to($event['start'], 'ts');
 		foreach($recurences as $date)
 		{
 			$startts = $date->format('ts');