This DEV-only field was added in 836331ba5f69f2cc53b273ec073fae116db14302 by @sebmarkbage but it's not being used anymore to my knowledge.
Component,
        resolveDefaultProps(Component.type, resolvedProps), 
        updateLanes,
        renderLanes,
      );
      return child;
    }
  }
  let hint = '';
  if (__DEV__) {
    if (
      Component !== null &&
      typeof Component === 'object' &&
      Component.$$typeof === REACT_LAZY_TYPE
    ) {
      hint = ' Did you wrap a component in React.lazy() more than once?';
    }
  }
  
  
  
  invariant(
    false,
    'Element type is invalid. Received a promise that resolves to: %s. ' +
      'Lazy element type must resolve to a class or function.%s',
    Component,
    hint,
  );
}
function mountIncompleteClassComponent(