From 9dde97d77889671d5073ad0b27647cfd60db1976 Mon Sep 17 00:00:00 2001
From: Matthias Schmidt <gravatronics@live.com>
Date: Mon, 15 Oct 2018 19:13:37 +0200
Subject: [PATCH] Fix `XML::write()` for comments in root element

See #2545
---
 wcfsetup/install/files/lib/util/XML.class.php | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/wcfsetup/install/files/lib/util/XML.class.php b/wcfsetup/install/files/lib/util/XML.class.php
index d22b19941f..ddaf98001f 100644
--- a/wcfsetup/install/files/lib/util/XML.class.php
+++ b/wcfsetup/install/files/lib/util/XML.class.php
@@ -224,7 +224,10 @@ class XML {
 			$this->getAttributes($this->document->documentElement)
 		);
 		foreach ($this->document->documentElement->childNodes as $childNode) {
-			$this->writeElement($writer, $childNode, $cdata);
+			// only consider dom elements, ignore comments
+			if ($childNode instanceof \DOMElement) {
+				$this->writeElement($writer, $childNode, $cdata);
+			}
 		}
 		$writer->endDocument($fileLocation);
 	}
-- 
2.20.1