From 99a150a0083e156e26f08f6dd21424c031827167 Mon Sep 17 00:00:00 2001
From: Olli Pettay <Olli.Pettay@helsinki.fi>
Date: Wed, 6 Aug 2025 18:37:49 +0000
Subject: [PATCH] Bug 1828622, try to stabilize test_focus.xhtml a bit, r=farre
 a=test-only

Differential Revision: https://phabricator.services.mozilla.com/D259856
---
 dom/tests/mochitest/chrome/window_focus.xhtml | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/dom/tests/mochitest/chrome/window_focus.xhtml b/dom/tests/mochitest/chrome/window_focus.xhtml
index 72759465a51d..bb119ae4a456 100644
--- a/dom/tests/mochitest/chrome/window_focus.xhtml
+++ b/dom/tests/mochitest/chrome/window_focus.xhtml
@@ -1572,8 +1572,13 @@ function doFrameHistoryTests()
           resolve({ location: content.location.href, persisted });
         }, { once: true });
       });
-      // make sure that loading a new page and then going back maintains the focus
-      content.location = "data:text/html,<script>window.onload=function() {setTimeout(function () { history.back() }, 0);}</script>";
+      // Make sure that loading a new page and then going back maintains the focus,
+      // but try to stabilize the page first so that it can enter bfcache.
+      content.requestAnimationFrame(() => {
+        content.requestAnimationFrame(() => {
+          content.location = "data:text/html,<script>window.onload=function() {setTimeout(function () { history.back() }, 0);}</script>";
+        });
+      });
       return goneBack;
     });
   }).then(({ location, persisted }) => {