From 69dc4fa5e018a874b69a554704e128847acbf460 Mon Sep 17 00:00:00 2001
From: Ian Paschal <i.paschal@ultimaker.com>
Date: Tue, 13 Mar 2018 09:20:42 +0100
Subject: [PATCH] Concerning the unfortunate crash...

..of the morning of the 13th day of March, in the 2018th year of our lord.
---
 cura/Settings/MachineManager.py | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/cura/Settings/MachineManager.py b/cura/Settings/MachineManager.py
index afff8b96b3..75024ad395 100755
--- a/cura/Settings/MachineManager.py
+++ b/cura/Settings/MachineManager.py
@@ -875,6 +875,8 @@ class MachineManager(QObject):
 
     @pyqtProperty("QVariantList", notify = globalContainerChanged)
     def currentExtruderPositions(self):
+        if self._global_container_stack is None:
+            return []
         return sorted(list(self._global_container_stack.extruders.keys()))
 
     ##  Update _current_root_material_id and _current_root_material_name when