Given
```js
function ThrowInEffect() {
  React.useEffect(() => {
    throw new Error('passive effect')
  }, [])
  return null;
}
```

In React 17 this error got logged to the console (and triggered the error overlay in create-react-app) regardless of whether `ThrowInEffect` was a child of an Error Boundary or not.

In React 18 (`createRoot` and legacy root API) an Error Boundary will prevent logging that error to the console (and not trigger the error overlay in create-react-app).

Errors during render work like they did in React 17.

Behavior in React 17: https://codesandbox.io/s/react-17-error-boundaries-vp21e?file=/src/index.js
Behavior in React 18: https://codesandbox.io/s/react-18-error-boundaries-psd56?file=/src/index.js


Recording of effect errors in React 17 and 18 and with and without Error Boundaries_

https://user-images.githubusercontent.com/12292047/122749780-053ced00-d28e-11eb-98ce-075dcdc53ee2.mp4


subtreeRoot: Fiber,
  root: FiberRoot,
  committedLanes: Lanes,
) {
  
  const isModernRoot = (subtreeRoot.mode & ConcurrentMode) !== NoMode;
  while (nextEffect !== null) {
    const fiber = nextEffect;
    const firstChild = fiber.child;
    if (
      enableSuspenseLayoutEffectSemantics &&
      fiber.tag === OffscreenComponent &&
      isModernRoot
    ) {
       
      const isHidden = fiber.memoizedState !== null;
      const newOffscreenSubtreeIsHidden = isHidden || offscreenSubtreeIsHidden;
      if (newOffscreenSubtreeIsHidden) {
         
        commitLayoutMountEffects_complete(subtreeRoot, root, committedLanes);
        continue;
      } else {
         
        const current = fiber.alternate;
        const wasHidden = current !== null && current.memoizedState !== null;
        const newOffscreenSubtreeWasHidden =
          wasHidden || offscreenSubtreeWasHidden;
        const prevOffscreenSubtreeIsHidden = offscreenSubtreeIsHidden;
        const prevOffscreenSubtreeWasHidden = offscreenSubtreeWasHidden;