diff --git a/cura/Settings/CuraContainerStack.py b/cura/Settings/CuraContainerStack.py
index ca4f866598..308a91bc76 100755
--- a/cura/Settings/CuraContainerStack.py
+++ b/cura/Settings/CuraContainerStack.py
@@ -283,6 +283,13 @@ class CuraContainerStack(ContainerStack):
 
         self._containers = new_containers
 
+        # CURA-5281
+        # Some stacks can have empty definition_changes containers which will cause problems.
+        # Make sure that all stacks here have non-empty definition_changes containers.
+        if isinstance(new_containers[_ContainerIndexes.DefinitionChanges], type(self._empty_instance_container)):
+            from cura.Settings.CuraStackBuilder import CuraStackBuilder
+            CuraStackBuilder.createDefinitionChangesContainer(self, self.getId() + "_settings")
+
     ## protected:
 
     # Helper to make sure we emit a PyQt signal on container changes.
diff --git a/cura/Settings/MachineManager.py b/cura/Settings/MachineManager.py
index 1d6d339e29..14f4f5fc33 100755
--- a/cura/Settings/MachineManager.py
+++ b/cura/Settings/MachineManager.py
@@ -302,13 +302,6 @@ class MachineManager(QObject):
 
     ## Given a global_stack, make sure that it's all valid by searching for this quality group and applying it again
     def _initMachineState(self, global_stack):
-        # Some stacks can have empty definition_changes containers which will cause problems.
-        # Make sure that all stacks here have non-empty definition_changes containers.
-        for stack in [global_stack] + list(global_stack.extruders.values()):
-            if isinstance(stack.definitionChanges, type(self._empty_container)):
-                from cura.Settings.CuraStackBuilder import CuraStackBuilder
-                CuraStackBuilder.createDefinitionChangesContainer(stack, stack.getId() + "_settings")
-
         material_dict = {}
         for position, extruder in global_stack.extruders.items():
             material_dict[position] = extruder.material.getMetaDataEntry("base_file")
diff --git a/plugins/PluginBrowser/PluginBrowser.py b/plugins/PluginBrowser/PluginBrowser.py
index 8c91d5a4be..bf18aa7a86 100644
--- a/plugins/PluginBrowser/PluginBrowser.py
+++ b/plugins/PluginBrowser/PluginBrowser.py
@@ -309,8 +309,12 @@ class PluginBrowser(QObject, Extension):
         try:
             plugin_object = self._plugin_registry.getPluginObject(plugin_id)
         except PluginNotFoundError:
+            # CURA-5287
+            # At this point, we know that this plugin is installed because it passed the previous check, but we cannot
+            # get the PluginObject. This means there is a bug in the plugin or something. So, we always allow to upgrade
+            # this plugin and hopefully that fixes it.
             Logger.log("w", "Could not find plugin %s", plugin_id)
-            return False
+            return True
 
         # Scan plugin server data for plugin with the given id:
         for plugin in self._plugins_metadata: