See #17798
nextFiber,
          traceNearestHostComponentUpdate,
        )
      ) {
        shouldResetChildren = true;
      }
    } else if (prevDidTimeout && !nextDidTimeOut) {
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       1
       N
       2
      const nextPrimaryChildSet = nextFiber.child;
      if (nextPrimaryChildSet !== null) {
        mountFiberRecursively(
          nextPrimaryChildSet,
          nextFiber,
          true,
          traceNearestHostComponentUpdate,
        );
      }
      shouldResetChildren = true;
    } else if (!prevDidTimeout && nextDidTimeOut) {
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       1
       T
       W
      unmountFiberChildrenRecursively(prevFiber);
       2
      const nextFiberChild = nextFiber.child;
      const nextFallbackChildSet = nextFiberChild