docs: add detail a example when useMemo/useCallback result will change.

src/content/reference/react/useCallback.md

@@ -51,7 +51,7 @@ During subsequent renders, it will either return an already stored `fn` functio
 #### Caveats {/*caveats*/}
 
 * `useCallback` is a Hook, so you can only call it **at the top level of your component** or your own Hooks. You can't call it inside loops or conditions. If you need that, extract a new component and move the state into it.
-* React **will not throw away the cached function unless there is a specific reason to do that.** For example, in development, React throws away the cache when you edit the file of your component. Both in development and in production, React will throw away the cache if your component suspends during the initial mount. In the future, React may add more features that take advantage of throwing away the cache--for example, if React adds built-in support for virtualized lists in the future, it would make sense to throw away the cache for items that scroll out of the virtualized table viewport. This should match your expectations if you rely on `useCallback` as a performance optimization. Otherwise, a [state variable](/reference/react/useState#im-trying-to-set-state-to-a-function-but-it-gets-called-instead) or a [ref](/reference/react/useRef#avoiding-recreating-the-ref-contents) may be more appropriate.
+* React **will not throw away the cached function unless there is a specific reason to do that.** For example, component or parent component key has change; in development, React throws away the cache when you edit the file of your component. Both in development and in production, React will throw away the cache if your component suspends during the initial mount. In the future, React may add more features that take advantage of throwing away the cache--for example, if React adds built-in support for virtualized lists in the future, it would make sense to throw away the cache for items that scroll out of the virtualized table viewport. This should match your expectations if you rely on `useCallback` as a performance optimization. Otherwise, a [state variable](/reference/react/useState#im-trying-to-set-state-to-a-function-but-it-gets-called-instead) or a [ref](/reference/react/useRef#avoiding-recreating-the-ref-contents) may be more appropriate.
 
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src/content/reference/react/useMemo.md

@@ -52,7 +52,7 @@ During next renders, it will either return an already stored value from the last
 
 * `useMemo` is a Hook, so you can only call it **at the top level of your component** or your own Hooks. You can't call it inside loops or conditions. If you need that, extract a new component and move the state into it.
 * In Strict Mode, React will **call your calculation function twice** in order to [help you find accidental impurities.](#my-calculation-runs-twice-on-every-re-render) This is development-only behavior and does not affect production. If your calculation function is pure (as it should be), this should not affect your logic. The result from one of the calls will be ignored.
-* React **will not throw away the cached value unless there is a specific reason to do that.** For example, in development, React throws away the cache when you edit the file of your component. Both in development and in production, React will throw away the cache if your component suspends during the initial mount. In the future, React may add more features that take advantage of throwing away the cache--for example, if React adds built-in support for virtualized lists in the future, it would make sense to throw away the cache for items that scroll out of the virtualized table viewport. This should be fine if you rely on `useMemo` solely as a performance optimization. Otherwise, a [state variable](/reference/react/useState#avoiding-recreating-the-initial-state) or a [ref](/reference/react/useRef#avoiding-recreating-the-ref-contents) may be more appropriate.
+* React **will not throw away the cached value unless there is a specific reason to do that.** For example, component or parent component key has change; in development, React throws away the cache when you edit the file of your component. Both in development and in production, React will throw away the cache if your component suspends during the initial mount. In the future, React may add more features that take advantage of throwing away the cache--for example, if React adds built-in support for virtualized lists in the future, it would make sense to throw away the cache for items that scroll out of the virtualized table viewport. This should be fine if you rely on `useMemo` solely as a performance optimization. Otherwise, a [state variable](/reference/react/useState#avoiding-recreating-the-initial-state) or a [ref](/reference/react/useRef#avoiding-recreating-the-ref-contents) may be more appropriate.
 
 <Note>