Use when extending the Unreal Editor from C++ with detail customizations, editor utility widgets, menus, editor modes, asset definitions or editor subsystems. Also use when the user mentions 'IDetailCustomization', 'IPropertyTypeCustomization', 'CustomizeDetails', 'RegisterCustomClassLayout', 'IDetailLayoutBuilder', 'AddCustomRow', 'IPropertyHandle', 'UToolMenus', 'ExtendMenu', 'FToolMenuEntry', 'UEditorUtilityWidget', 'Blutility', 'UAssetActionUtility', 'UEditorSubsystem', 'UEdMode', 'UAssetDef

Use when writing or fixing Unreal Engine UI in C++ — UMG user widgets, Slate widgets, Common UI screens, or MVVM view models. Also use when the user mentions 'UUserWidget', 'NativeConstruct', 'BindWidget', 'CreateWidget', 'AddToViewport', 'ESlateVisibility', 'OnClicked', 'UListView', 'widget animation', 'SNew', 'SLATE_BEGIN_ARGS', 'SCompoundWidget', 'UCommonActivatableWidget', 'activatable widget stack', 'UCommonButtonBase', 'gamepad focus', 'FUIInputConfig', 'UMVVMViewModelBase', 'FieldNotify',