From 9ec83d5210f03c1fa4c66f97de89654f78a7c6cb Mon Sep 17 00:00:00 2001
From: David Kocik <kocikdav@gmail.com>
Date: Mon, 18 May 2020 08:28:53 +0200
Subject: [PATCH] instance check: bux fix in shutdown() - repairs falling at
 assert when reiniting otherInstanceMessageHandler

---
 src/slic3r/GUI/InstanceCheck.cpp | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/slic3r/GUI/InstanceCheck.cpp b/src/slic3r/GUI/InstanceCheck.cpp
index 2d1186270..4470876c7 100644
--- a/src/slic3r/GUI/InstanceCheck.cpp
+++ b/src/slic3r/GUI/InstanceCheck.cpp
@@ -298,7 +298,8 @@ void OtherInstanceMessageHandler::shutdown(MainFrame* main_frame)
 			m_stop = false;
 		}
 #endif //BACKGROUND_MESSAGE_LISTENER
-	m_initialized = false;
+		m_callback_evt_handler = nullptr;
+		m_initialized = false;
 	}
 }