From dd8140397a63a02508a5a913bdac0fc9bcf078de Mon Sep 17 00:00:00 2001
From: Hadi Nategh <hnategh@gmail.com>
Date: Fri, 14 Jan 2022 14:02:56 +0100
Subject: [PATCH] Fix error Argument #2 must be of type array, null given

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

diff --git a/calendar/inc/class.calendar_so.inc.php b/calendar/inc/class.calendar_so.inc.php
index 7959b51ed5..7a8a41f16c 100644
--- a/calendar/inc/class.calendar_so.inc.php
+++ b/calendar/inc/class.calendar_so.inc.php
@@ -2125,7 +2125,7 @@ ORDER BY cal_user_type, cal_usre_id
 				// for new or changed group-invitations, remove previously deleted members, so they show up again
 				if ($uid < 0)
 				{
-					$delete_deleted = array_merge($delete_deleted, $GLOBALS['egw']->accounts->members($uid, true));
+					$delete_deleted = array_merge($delete_deleted, (array)$GLOBALS['egw']->accounts->members($uid, true));
 				}
 			}
 			if ($delete_deleted)