From f8221777887c30d40f4e90f0b4729a87e2216bec Mon Sep 17 00:00:00 2001
From: Alex van Andel <me@alexvanandel.com>
Date: Mon, 14 Nov 2022 19:46:58 +0000
Subject: [PATCH] Use Intl.DateTimeFormat logic to determine locale. (#5519)

---
 packages/lib/timeFormat.ts | 9 ++-------
 1 file changed, 2 insertions(+), 7 deletions(-)

diff --git a/packages/lib/timeFormat.ts b/packages/lib/timeFormat.ts
index 6c66e8f575..ee6c71b1ea 100644
--- a/packages/lib/timeFormat.ts
+++ b/packages/lib/timeFormat.ts
@@ -31,13 +31,8 @@ export const isBrowserLocale24h = () => {
   } else if (localStorageTimeFormat === false) {
     return false;
   }
-
-  let locale = "en-US";
-  if (typeof window !== "undefined" && navigator) {
-    locale = window.navigator?.language;
-  }
-
-  if (!!new Intl.DateTimeFormat(locale, { hour: "numeric" }).format(0).match(/M/i)) {
+  // Intl.DateTimeFormat with value=undefined uses local browser settings.
+  if (!!new Intl.DateTimeFormat(undefined, { hour: "numeric" }).format(0).match(/M/i)) {
     setIs24hClockInLocalStorage(false);
     return false;
   } else {