Codex macOS app: cannot change UI language to English

I found a localization issue in the Codex macOS app: the UI language cannot be switched to English.

Steps to reproduce

1. Open Codex macOS app
2. Go to Settings/Preferences
3. Try to set UI language to English
4. Restart app if prompted

Expected
UI changes to English.

Actual
UI stays in the current language (or English is not selectable).

Environment

• macOS: [please fill your macOS version]
• Codex app version: 26.226.940 (720)

Co-op report by me with Codex assistant.