/usr/share/lemonldap-ng/portal-skins/common/js/browseridlogout.js is in liblemonldap-ng-portal-perl 1.9.16-2.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 | $(document).ready(function() {
navigator.id.logout();
});
|