This DEV-only field was added in 836331ba5f69f2cc53b273ec073fae116db14302 by @sebmarkbage but it's not being used anymore to my knowledge.
fiber.lanes = lanes;
  return fiber;
}
export function createFiberFromText(
  content: string,
  mode: TypeOfMode,
  lanes: Lanes,
): Fiber {
  const fiber = createFiber(HostText, content, null, mode);
  fiber.lanes = lanes;
  return fiber;
}
export function createFiberFromHostInstanceForDeletion(): Fiber {
  const fiber = createFiber(HostComponent, null, null, NoMode);
  fiber.elementType = 'DELETED';
  return fiber;
}
export function createFiberFromDehydratedFragment(
  dehydratedNode: SuspenseInstance,
): Fiber {
  const fiber = createFiber(DehydratedFragment, null, null, NoMode);
  fiber.stateNode = dehydratedNode;
  return fiber;
}
export function createFiberFromPortal(
  portal: ReactPortal,
  mode: TypeOfMode,
  lanes: Lanes,
): Fiber {
  const pendingProps = portal.children !== null ? portal.children : [];