This DEV-only field was added in 836331ba5f69f2cc53b273ec073fae116db14302 by @sebmarkbage but it's not being used anymore to my knowledge.
}
        }
      }
    }
    const nextPrimaryChildren = nextProps.children;
    const nextFallbackChildren = nextProps.fallback;
    if (showFallback) {
      const fallbackFragment = mountSuspenseFallbackChildren(
        workInProgress,
        nextPrimaryChildren,
        nextFallbackChildren,
        renderLanes,
      );
      const primaryChildFragment: Fiber = (workInProgress.child: any);
      primaryChildFragment.memoizedState = mountSuspenseOffscreenState(
        renderLanes,
      );
      workInProgress.memoizedState = SUSPENDED_MARKER;
      return fallbackFragment;
    } else if (typeof nextProps.unstable_expectedLoadTime === 'number') {
      
      
      
      const fallbackFragment = mountSuspenseFallbackChildren(
        workInProgress,
        nextPrimaryChildren,
        nextFallbackChildren,
        renderLanes,
      );
      const primaryChildFragment: Fiber = (workInProgress.child: any);