diff --git a/tests/Settings/TestExtruderStack.py b/tests/Settings/TestExtruderStack.py
index 41aefcbd05..c49448b030 100644
--- a/tests/Settings/TestExtruderStack.py
+++ b/tests/Settings/TestExtruderStack.py
@@ -263,6 +263,7 @@ def test_getPropertyFallThrough(extruder_stack):
     extruder_stack.variant = mock_no_settings[container_indices.Variant]
     with unittest.mock.patch("cura.Settings.CuraContainerStack.DefinitionContainer", unittest.mock.MagicMock): #To guard against the type checking.
         extruder_stack.definition = mock_layer_heights[container_indices.Definition] #There's a layer height in here!
+    extruder_stack.setNextStack(unittest.mock.MagicMock())
 
     assert extruder_stack.getProperty("layer_height", "value") == container_indices.Definition
     extruder_stack.variant = mock_layer_heights[container_indices.Variant]
@@ -382,4 +383,4 @@ def test_setVariantByIdExists(extruder_stack, container_registry):
 ##  Tests setting variants by specifying an ID of a variant that doesn't exist.
 def test_setVariantByIdDoesntExist(extruder_stack):
     with pytest.raises(InvalidContainerError):
-        extruder_stack.setVariantById("some_variant") #Container registry is empty now.
\ No newline at end of file
+        extruder_stack.setVariantById("some_variant") #Container registry is empty now.