From baf85f1daf1ce37597caf8031efca128ee198277 Mon Sep 17 00:00:00 2001
From: Matthias Schmidt <gravatronics@live.com>
Date: Mon, 17 Oct 2016 20:17:55 +0200
Subject: [PATCH] Fix previous commit

---
 wcfsetup/install/files/lib/acp/form/BoxEditForm.class.php | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/wcfsetup/install/files/lib/acp/form/BoxEditForm.class.php b/wcfsetup/install/files/lib/acp/form/BoxEditForm.class.php
index a86641f185..5af7580e97 100644
--- a/wcfsetup/install/files/lib/acp/form/BoxEditForm.class.php
+++ b/wcfsetup/install/files/lib/acp/form/BoxEditForm.class.php
@@ -126,7 +126,7 @@ class BoxEditForm extends BoxAddForm {
 			$oldController = new $className;
 			
 			/** @noinspection PhpUndefinedMethodInspection */
-			if ($oldController->getConditionDefinition() && (!$this->boxController || (!($this->boxController->getProcessor() instanceof IConditionBoxController)) || !$this->boxController->getProcessor()->getConditionDefinition())) {
+			if ($oldController instanceof IConditionBoxController && $oldController->getConditionDefinition() && (!$this->boxController || (!($this->boxController->getProcessor() instanceof IConditionBoxController)) || !$this->boxController->getProcessor()->getConditionDefinition())) {
 				ConditionHandler::getInstance()->deleteConditions($oldController->getConditionDefinition(), [$this->box->boxID]);
 			}
 		}
-- 
2.20.1