diff --git a/cura/CuraApplication.py b/cura/CuraApplication.py
index 7e6ef472c0..09f04d9a2d 100644
--- a/cura/CuraApplication.py
+++ b/cura/CuraApplication.py
@@ -86,10 +86,19 @@ class CuraApplication(QtApplication):
         # Need to do this before ContainerRegistry tries to load the machines
         SettingDefinition.addSupportedProperty("settable_per_mesh", DefinitionPropertyType.Any, default = True, read_only = True)
         SettingDefinition.addSupportedProperty("settable_per_extruder", DefinitionPropertyType.Any, default = True, read_only = True)
+        # this setting can be changed for each group in one-at-a-time mode
         SettingDefinition.addSupportedProperty("settable_per_meshgroup", DefinitionPropertyType.Any, default = True, read_only = True)
         SettingDefinition.addSupportedProperty("settable_globally", DefinitionPropertyType.Any, default = True, read_only = True)
+
+        # From which stack the setting would inherit if not defined per object (handled in the engine)
+        # AND for settings which are not settable_per_mesh:
+        # which extruder is the only extruder this setting is obtained from
         SettingDefinition.addSupportedProperty("limit_to_extruder", DefinitionPropertyType.Function, default = "-1")
+
+        # For settings which are not settable_per_mesh and not settable_per_extruder:
+        # A function which determines the glabel/meshgroup value by looking at the values of the setting in all (used) extruders
         SettingDefinition.addSupportedProperty("resolve", DefinitionPropertyType.Function, default = None)
+
         SettingDefinition.addSettingType("extruder", None, str, Validator)
 
         SettingFunction.registerOperator("extruderValues", cura.Settings.ExtruderManager.getExtruderValues)
diff --git a/plugins/CuraEngineBackend/Cura.proto b/plugins/CuraEngineBackend/Cura.proto
index d5407f22c8..4eab500f0a 100644
--- a/plugins/CuraEngineBackend/Cura.proto
+++ b/plugins/CuraEngineBackend/Cura.proto
@@ -13,7 +13,7 @@ message Slice
     repeated ObjectList object_lists = 1; // The meshgroups to be printed one after another
     SettingList global_settings = 2; // The global settings used for the whole print job
     repeated Extruder extruders = 3; // The settings sent to each extruder object
-    repeated SettingExtruder limit_to_extruder = 4; //From which stack the setting would inherit if not defined in a stack.
+    repeated SettingExtruder limit_to_extruder = 4; // From which stack the setting would inherit if not defined per object
 }
 
 message Extruder