Merge branch 'main' of https://github.com/reactjs/react.dev into sync-a1cc2ab4

Author: react-translations-bot

.gitignore

@@ -43,3 +43,6 @@ public/rss.xml
 # claude local settings
 .claude/*.local.*
 .claude/react/
+
+# worktrees
+.worktrees/

src/content/blog/2025/12/11/denial-of-service-and-source-code-exposure-in-react-server-components.md

@@ -106,7 +106,7 @@ See [this issue](https://github.com/facebook/react-native/issues/54772#issuecomm
 
 **CVEs:** [CVE-2026-23864](https://www.cve.org/CVERecord?id=CVE-2026-23864)
 **Base Score:** 7.5 (High)
-**Date**: January 26, 2025
+**Date**: January 26, 2026
 
 Security researchers discovered additional DoS vulnerabilities still exist in React Server Components.
 

src/content/reference/react/Activity.md

@@ -48,7 +48,7 @@ In this way, Activity can be thought of as a mechanism for rendering "background
 #### Caveats {/*caveats*/}
 
 - If an Activity is rendered inside of a [ViewTransition](/reference/react/ViewTransition), and it becomes visible as a result of an update caused by [startTransition](/reference/react/startTransition), it will activate the ViewTransition's `enter` animation. If it becomes hidden, it will activate its `exit` animation.
-- An Activity that just renders text will not render anything rather than rendering hidden text, because there’s no corresponding DOM element to apply visibility changes to. For example, `<Activity mode="hidden"><ComponentThatJustReturnsText /></Activity>` will not produce any output in the DOM for `const ComponentThatJustReturnsText = () => "Hello, World!"`.
+- A *hidden* Activity that just renders text will not render anything rather than rendering hidden text, because there’s no corresponding DOM element to apply visibility changes to. For example, `<Activity mode="hidden"><ComponentThatJustReturnsText /></Activity>` will not produce any output in the DOM for `const ComponentThatJustReturnsText = () => "Hello, World!"`. `<Activity mode="visible"><ComponentThatJustReturnsText /></Activity>` will render visible text.
 
 ---
 

src/content/reference/react/hooks.md

@@ -79,6 +79,9 @@ There are two rarely used variations of `useEffect` with differences in timing:
 * [`useLayoutEffect`](/reference/react/useLayoutEffect) fires before the browser repaints the screen. You can measure layout here.
 * [`useInsertionEffect`](/reference/react/useInsertionEffect) fires before React makes changes to the DOM. Libraries can insert dynamic CSS here.
 
+You can also separate events from Effects:
+
+- [`useEffectEvent`](/reference/react/useEffectEvent) creates a non-reactive event to fire from any Effect hook.
 ---
 
 ## Performance Hooks {/*performance-hooks*/}