pad.libre-service.eu-etherpad/src/static/js/l10n.js

(function (document) {
  // Set language for l10n
  let language = document.cookie.match(/language=((\w{2,3})(-\w+)?)/);
  if (language) language = language[1];

  html10n.bind('indexed', () => {
    html10n.localize([language, navigator.language, navigator.userLanguage, 'en']);
  });

  html10n.bind('localized', () => {
    document.documentElement.lang = html10n.getLanguage();
    document.documentElement.dir = html10n.getDirection();
  });
})(document);