See #17798
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    const prevDidTimeout = isSuspense && prevFiber.memoizedState !== null;
    const nextDidTimeOut = isSuspense && nextFiber.memoizedState !== null;
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    if (prevDidTimeout && nextDidTimeOut) {
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      const nextFiberChild = nextFiber.child;
      const nextFallbackChildSet = nextFiberChild
        ? nextFiberChild.sibling
        : null;
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      const prevFiberChild = prevFiber.child;
      const prevFallbackChildSet = prevFiberChild
        ? prevFiberChild.sibling
        : null;
      if (
        nextFallbackChildSet != null &&
        prevFallbackChildSet != null &&
        updateFiberRecursively(
          nextFallbackChildSet,
          prevFallbackChildSet,