| string, type: any, stateNode: any, return: Fiber | null, child: Fiber | null, sibling: Fiber | null, index: number, ref: null | (((handle: mixed) => void) & {_stringRef: ?string}), pendingProps: any, // This type will be more specific once we overload the tag. memoizedProps: any, // The props used to create the output. updateQueue: UpdateQueue | null, memoizedState: any, internalContextTag: TypeOfInternalContext, effectTag: TypeOfSideEffect, nextEffect: Fiber | null, firstEffect: Fiber | null, lastEffect: Fiber | null, pendingWorkPriority: PriorityLevel, progressedPriority: PriorityLevel, progressedChild: Fiber | null, progressedFirstDeletion: Fiber | null, progressedLastDeletion: Fiber | null, alternate: Fiber | null, };