This DEV-only field was added in 836331ba5f69f2cc53b273ec073fae116db14302 by @sebmarkbage but it's not being used anymore to my knowledge.
const hasContextChanged = includesSomeLane(renderLanes, current.childLanes);
  if (didReceiveUpdate || hasContextChanged) {
    
    
    const root = getWorkInProgressRoot();
    if (root !== null) {
      const attemptHydrationAtLane = getBumpedLaneForHydration(
        root,
        renderLanes,
      );
      if (
        attemptHydrationAtLane !== NoLane &&
        attemptHydrationAtLane !== suspenseState.retryLane
      ) {
        
        
        
        suspenseState.retryLane = attemptHydrationAtLane;
        
        const eventTime = NoTimestamp;
        scheduleUpdateOnFiber(current, attemptHydrationAtLane, eventTime);
      } else {
        
        
        
        
        
        
      }
    }