<?php
$config = [
    'components' => [
        'request' => [
            // !!! insert a secret key in the following (if it is empty) - this is required by cookie validation

            'cookieValidationKey' => 'YdCyYvm8eOZZsaNRa_idrGimyTbsEQ8R',

        ],
    ],
];

return $config;