From 6943c4decbcf552f3845cff5ddfac96e9e1688e1 Mon Sep 17 00:00:00 2001
From: chungyo <kimchungy98@gachon.ac.kr>
Date: Wed, 9 Sep 2026 22:10:41 +0900
Subject: [PATCH] docs: explain Chrome focus emulation in window focus
 refetching guide

---
 docs/framework/react/guides/window-focus-refetching.md | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/docs/framework/react/guides/window-focus-refetching.md b/docs/framework/react/guides/window-focus-refetching.md
index b2a4cbd3e5c..1691c166ff7 100644
--- a/docs/framework/react/guides/window-focus-refetching.md
+++ b/docs/framework/react/guides/window-focus-refetching.md
@@ -103,3 +103,9 @@ focusManager.setFocused(undefined)
 ```
 
 [//]: # 'Example4'
+
+## Troubleshooting
+
+If stale queries do not refetch when you return to a tab, check whether **Emulate a focused page** is enabled in Chrome DevTools. This setting keeps `document.visibilityState` set to `visible` and prevents `visibilitychange` events, which TanStack Query uses for its default focus handling.
+
+Disable **Emulate a focused page** in the DevTools **Rendering** panel, then switch to another tab and return to test window focus refetching. See the [Chrome DevTools documentation](https://developer.chrome.com/docs/devtools/rendering/apply-effects#emulate_a_focused_page) for more details.