Batched state changes are not flushed if the promise code changes the DOM (= attaching an iframe). Reproduceable with Safari.

React version: 18.1.0

## Steps To Reproduce

1. Open [codepen](https://codepen.io/kh-viewar/pen/wvpVLxM) with Safari.
2. Click "Upload"
3. => "Spinner" text does not render while Promise is in pending

Link to code example:

https://codepen.io/kh-viewar/pen/wvpVLxM

## The current behavior

State changes are not executed.

## The expected behavior

State should change to true and render spinner component. After promise is resolved (2 seconds timeout), state should switch back to false and spinner component should unmount.

## Original discussion

https://github.com/facebook/react/issues/24365
while (workInProgress !== null && !shouldYield()) {
    performUnitOfWork(workInProgress);
  }
}
function performUnitOfWork(unitOfWork: Fiber): void {
   
   
   
  const current = unitOfWork.alternate;
  setCurrentDebugFiberInDEV(unitOfWork);
  let next;
  if (enableProfilerTimer && (unitOfWork.mode & ProfileMode) !== NoMode) {
    startProfilerTimer(unitOfWork);
    next = beginWork(current, unitOfWork, subtreeRenderLanes);
    stopProfilerTimerIfRunningAndRecordDelta(unitOfWork, true);
  } else {
    next = beginWork(current, unitOfWork, subtreeRenderLanes);
  }
  resetCurrentDebugFiberInDEV();
  unitOfWork.memoizedProps = unitOfWork.pendingProps;
  if (next === null) {
     
    completeUnitOfWork(unitOfWork);
  } else {
    workInProgress = next;
  }
  ReactCurrentOwner.current = null;
}
function completeUnitOfWork(unitOfWork: Fiber): void {