Call operator for objc.ObjCBlock<NSMenu? Function(ffi.Pointer<ffi.Void>)>.
objc.ObjCBlock<NSMenu? Function(ffi.Pointer<ffi.Void>)>
Available on ObjCBlock<NSMenu? Function(Pointer<Void>)>, provided by the ObjCBlock_NSMenu_ffiVoid_CallExtension extension