diff --git a/cura/UI/GlobalStacksModel.py b/cura/UI/GlobalStacksModel.py
index 579555e52c..f15fe1878b 100644
--- a/cura/UI/GlobalStacksModel.py
+++ b/cura/UI/GlobalStacksModel.py
@@ -29,7 +29,6 @@ class GlobalStacksModel(ListModel):
         self.addRoleName(self.HasRemoteConnectionRole, "hasRemoteConnection")
         self.addRoleName(self.MetaDataRole, "metadata")
         self.addRoleName(self.DiscoverySourceRole, "discoverySource")
-        self._container_stacks = []
 
         self._change_timer = QTimer()
         self._change_timer.setInterval(200)
@@ -40,7 +39,6 @@ class GlobalStacksModel(ListModel):
         CuraContainerRegistry.getInstance().containerAdded.connect(self._onContainerChanged)
         CuraContainerRegistry.getInstance().containerMetaDataChanged.connect(self._onContainerChanged)
         CuraContainerRegistry.getInstance().containerRemoved.connect(self._onContainerChanged)
-        self._filter_dict = {}
         self._updateDelayed()
 
     ##  Handler for container added/removed events from registry
diff --git a/cura/UI/MaterialOutputModel.py b/cura/UI/MaterialOutputModel.py
index b3dd83fb72..7a17ef3cce 100644
--- a/cura/UI/MaterialOutputModel.py
+++ b/cura/UI/MaterialOutputModel.py
@@ -1,11 +1,13 @@
 # Copyright (c) 2017 Ultimaker B.V.
 # Cura is released under the terms of the LGPLv3 or higher.
 
+from typing import Optional
+
 from PyQt5.QtCore import pyqtProperty, QObject
 
 
 class MaterialOutputModel(QObject):
-    def __init__(self, guid: str, type: str, color: str, brand: str, name: str, parent = None):
+    def __init__(self, guid: Optional[str], type: str, color: str, brand: str, name: str, parent = None) -> None:
         super().__init__(parent)
         self._guid = guid
         self._type = type
@@ -15,7 +17,7 @@ class MaterialOutputModel(QObject):
 
     @pyqtProperty(str, constant = True)
     def guid(self) -> str:
-        return self._guid
+        return self._guid if self._guid else ""
 
     @pyqtProperty(str, constant = True)
     def type(self) -> str:
diff --git a/cura/UI/ObjectsModel.py b/cura/UI/ObjectsModel.py
index 4d0233f6cb..09304451a5 100644
--- a/cura/UI/ObjectsModel.py
+++ b/cura/UI/ObjectsModel.py
@@ -2,6 +2,7 @@
 # Cura is released under the terms of the LGPLv3 or higher.
 
 from collections import defaultdict
+from typing import Dict
 
 from PyQt5.QtCore import QTimer
 
@@ -18,7 +19,7 @@ catalog = i18nCatalog("cura")
 
 ##  Keep track of all objects in the project
 class ObjectsModel(ListModel):
-    def __init__(self):
+    def __init__(self) -> None:
         super().__init__()
 
         Application.getInstance().getController().getScene().sceneChanged.connect(self._updateSceneDelayed)
@@ -48,7 +49,7 @@ class ObjectsModel(ListModel):
         filter_current_build_plate = Application.getInstance().getPreferences().getValue("view/filter_current_build_plate")
         active_build_plate_number = self._build_plate_number
         group_nr = 1
-        name_count_dict = defaultdict(int)
+        name_count_dict = defaultdict(int)  # type: Dict[str, int]
 
         for node in DepthFirstIterator(Application.getInstance().getController().getScene().getRoot()):
             if not isinstance(node, SceneNode):
diff --git a/plugins/UM3NetworkPrinting/src/UM3OutputDevicePlugin.py b/plugins/UM3NetworkPrinting/src/UM3OutputDevicePlugin.py
index 2bc79a5156..5a41bfa72b 100644
--- a/plugins/UM3NetworkPrinting/src/UM3OutputDevicePlugin.py
+++ b/plugins/UM3NetworkPrinting/src/UM3OutputDevicePlugin.py
@@ -27,9 +27,17 @@ from UM.Version import Version
 from . import ClusterUM3OutputDevice, LegacyUM3OutputDevice
 from .Cloud.CloudOutputDeviceManager import CloudOutputDeviceManager
 
+<<<<<<< HEAD
 if TYPE_CHECKING:
     from cura.Settings.GlobalStack import GlobalStack
     from UM.OutputDevice.OutputDevicePlugin import OutputDevicePlugin
+=======
+from typing import Optional, TYPE_CHECKING
+
+if TYPE_CHECKING:
+    from cura.Settings.GlobalStack import GlobalStack
+
+>>>>>>> origin/WIP_onboarding
 
 i18n_catalog = i18nCatalog("cura")
 
@@ -450,9 +458,8 @@ class UM3OutputDevicePlugin(OutputDevicePlugin):
         Logger.log("d", "Checking if cloud connection is possible...")
 
         # Pre-Check: Skip if active machine already has been cloud connected or you said don't ask again
-        active_machine = self._application.getMachineManager().activeMachine # type: Optional[GlobalStack]
+        active_machine = self._application.getMachineManager().activeMachine  # type: Optional[GlobalStack]
         if active_machine:
-            
             # Check 1A: Printer isn't already configured for cloud
             if ConnectionType.CloudConnection.value in active_machine.configuredConnectionTypes:
                 Logger.log("d", "Active machine was already configured for cloud.")