;NAMES = English,简体中文,繁體中文(香港),繁體中文(台灣),Deutsch,français,Nederlands,latviešu,русский,Українська,日本語,español,português do Brasil,Português de Portugal,polski,български,italiano,suomi,Türkçe,čeština,српски,svenska,한국어,ελληνικά,فارسی,magyar nyelv,bahasa Indonesia,മലയാളം
;NAMES = English,简体中文,繁體中文(香港),繁體中文(台灣),Deutsch,Français,Nederlands,Latviešu,Русский,Українська,日本語,Español,Português do Brasil,Português de Portugal,Polski,Български,Italiano,Suomi,Türkçe,Čeština,Српски,Svenska,한국어,Ελληνικά,فارسی,Magyar nyelv,Bahasa Indonesia,മലയാളം
List of locales shown in language selector. The first locale will be used as the default if user browser's language doesn't match any locale in the list.
- `NAMES`: **English,简体中文,繁體中文(香港),繁體中文(台灣),Deutsch,français,Nederlands,latviešu,русский,日本語,español,português do Brasil,Português de Portugal,polski,български,italiano,suomi,Türkçe,čeština,српски,svenska,한국어,ελληνικά,فارسی,magyar nyelv,bahasa Indonesia,മലയാളം**: Visible names corresponding to the locales
- `NAMES`: **English,简体中文,繁體中文(香港),繁體中文(台灣),Deutsch,Français,Nederlands,Latviešu,Русский,Українська,日本語,Español,Português do Brasil,Português de Portugal,Polski,Български,Italiano,Suomi,Türkçe,Čeština,Српски,Svenska,한국어,Ελληνικά,فارسی,Magyar nyelv,Bahasa Indonesia,മലയാളം**: Visible names corresponding to the locales
## U2F (`U2F`) **DEPRECATED**
- `APP_ID`: **`ROOT_URL`**: Declares the facet of the application which is used for authentication of previously registered U2F keys. Requires HTTPS.