From b18b1d3cd0abc1a4ad4635503c6f6d63852b84fe Mon Sep 17 00:00:00 2001
From: Jaime van Kessel <nallath@gmail.com>
Date: Tue, 6 Jun 2017 15:42:49 +0200
Subject: [PATCH] Only disable timer of backend if it's initialised

Fixes #1939
---
 plugins/MachineSettingsAction/MachineSettingsAction.py | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/plugins/MachineSettingsAction/MachineSettingsAction.py b/plugins/MachineSettingsAction/MachineSettingsAction.py
index 983b70d174..950c97a4e2 100755
--- a/plugins/MachineSettingsAction/MachineSettingsAction.py
+++ b/plugins/MachineSettingsAction/MachineSettingsAction.py
@@ -69,8 +69,9 @@ class MachineSettingsAction(MachineAction):
             self._container_index = container_index
             self.containerIndexChanged.emit()
 
-        # Disable autoslicing while the machineaction is showing
-        self._backend.disableTimer()
+        # Disable auto-slicing while the MachineAction is showing
+        if self._backend:  # This sometimes triggers before backend is loaded.
+            self._backend.disableTimer()
 
     @pyqtSlot()
     def onFinishAction(self):