diff --git a/cura/MachineActionManager.py b/cura/MachineActionManager.py
index 74b1d3bd08..ad9c91ec46 100644
--- a/cura/MachineActionManager.py
+++ b/cura/MachineActionManager.py
@@ -105,7 +105,7 @@ class MachineActionManager(QObject):
         if definition_id in self._supported_actions:
             return list(self._supported_actions[definition_id])
         else:
-            return set()
+            return list()
 
     ##  Get all actions required by given machine
     #   \param definition_id The ID of the definition you want the required actions of