diff --git a/cura/Machines/QualityManager.py b/cura/Machines/QualityManager.py
index a9aa6e9dcf..eb8a3611c1 100644
--- a/cura/Machines/QualityManager.py
+++ b/cura/Machines/QualityManager.py
@@ -256,7 +256,6 @@ class QualityManager(QObject):
 
     # Returns a dict of "custom profile name" -> QualityChangesGroup
     def getQualityChangesGroups(self, machine: "GlobalStack") -> dict:
-        # TODO: How to make this simpler?
         # Get machine definition ID for quality search
         machine_definition_id = getMachineDefinitionIDForQualitySearch(machine)
 
@@ -280,7 +279,6 @@ class QualityManager(QObject):
         return quality_changes_group_dict
 
     def getQualityGroups(self, machine: "GlobalStack") -> dict:
-        # TODO: How to make this simpler, including the fall backs.
         # Get machine definition ID for quality search
         machine_definition_id = getMachineDefinitionIDForQualitySearch(machine)
         # This determines if we should only get the global qualities for the global stack and skip the global qualities for the extruder stacks
diff --git a/cura/Settings/CuraStackBuilder.py b/cura/Settings/CuraStackBuilder.py
index 9273b272c1..4d103d2537 100644
--- a/cura/Settings/CuraStackBuilder.py
+++ b/cura/Settings/CuraStackBuilder.py
@@ -27,9 +27,9 @@ class CuraStackBuilder:
     def createMachine(cls, name: str, definition_id: str) -> Optional[GlobalStack]:
         from cura.CuraApplication import CuraApplication
         application = CuraApplication.getInstance()
-        variant_manager = CuraApplication.getInstance()._variant_manager
-        material_manager = CuraApplication.getInstance()._material_manager
-        quality_manager = CuraApplication.getInstance()._quality_manager
+        variant_manager = application.getVariantManager()
+        material_manager = application.getMaterialManager()
+        quality_manager = application.getQualityManager()
         registry = ContainerRegistry.getInstance()
 
         definitions = registry.findDefinitionContainers(id = definition_id)
diff --git a/plugins/3MFReader/ThreeMFReader.py b/plugins/3MFReader/ThreeMFReader.py
index 80ef913b54..95d8146d32 100755
--- a/plugins/3MFReader/ThreeMFReader.py
+++ b/plugins/3MFReader/ThreeMFReader.py
@@ -122,10 +122,10 @@ class ThreeMFReader(MeshReader):
                     um_node.callDecoration("setActiveExtruder", default_stack.getId())
 
                 # Get the definition & set it
-                definition_id = getMachineDefinitionIDForQualitySearch(global_container_stack.definition)
-                um_node.callDecoration("getStack").userChanges.setDefinition(definition_id)
+                definition_id = getMachineDefinitionIDForQualitySearch(global_container_stack)
+                um_node.callDecoration("getStack").getTop().setDefinition(definition_id)
 
-            setting_container = um_node.callDecoration("getStack").userChanges
+            setting_container = um_node.callDecoration("getStack").getTop()
 
             for key in settings:
                 setting_value = settings[key]