ot_typo3/ot_admin/ext_localconf.php

<?php
defined('TYPO3_MODE') || die();

// Because of this issue https://forge.typo3.org/issues/89449,
// we have to xclass the BackendUserAuthenticator backend middleware
// to allow routes to be public (but restricted to authorized ips)
$GLOBALS['TYPO3_CONF_VARS']['SYS']['Objects'][TYPO3\CMS\Backend\Middleware\BackendUserAuthenticator::class] = [
    'className' => Opentalent\OtAdmin\Middleware\OtBackendUserAuthenticator::class
];