diff --git a/cura/Settings/ContainerManager.py b/cura/Settings/ContainerManager.py
index 9cbd93555a..74d5d5f53a 100644
--- a/cura/Settings/ContainerManager.py
+++ b/cura/Settings/ContainerManager.py
@@ -333,16 +333,15 @@ class ContainerManager(QObject):
     @pyqtSlot(str, result = bool)
     def isContainerUsed(self, container_id):
         Logger.log("d", "Checking if container %s is currently used", container_id)
-        # check if this is a material container. If so, check if any material with the same GUID is being used by any
+        # check if this is a material container. If so, check if any material with the same base is being used by any
         # stacks.
         container_ids_to_check = [container_id]
         container_results = self._container_registry.findInstanceContainers(id = container_id, type = "material")
         if container_results:
             this_container = container_results[0]
-            container_guid = this_container.getMetaDataEntry("GUID")
-            # check all material container IDs with the same GUID
-            material_containers = self._container_registry.findInstanceContainers(id = container_id,
-                                                                                  GUID = container_guid,
+            material_base_file = this_container.getMetaDataEntry("base_file", this_container.getId())
+            # check all material container IDs with the same base
+            material_containers = self._container_registry.findInstanceContainers(base_file = material_base_file,
                                                                                   type = "material")
             if material_containers:
                 container_ids_to_check = [container.getId() for container in material_containers]
diff --git a/resources/definitions/fdmprinter.def.json b/resources/definitions/fdmprinter.def.json
index bdb95a6de3..b4a1a23028 100755
--- a/resources/definitions/fdmprinter.def.json
+++ b/resources/definitions/fdmprinter.def.json
@@ -1514,7 +1514,7 @@
                     "description": "Print the infill before printing the walls. Printing the walls first may lead to more accurate walls, but overhangs print worse. Printing the infill first leads to sturdier walls, but the infill pattern might sometimes show through the surface.",
                     "type": "bool",
                     "default_value": true,
-                    "enabled": "infill_sparse_density > 0 and wall_extruder_nr == infill_extruder_nr",
+                    "enabled": "infill_sparse_density > 0 and wall_x_extruder_nr == infill_extruder_nr",
                     "settable_per_mesh": true
                 },
                 "min_infill_area":