PHP Core Warning – yii\base\ErrorException

$_GET = [
    'random' => '1791966979',
];

$_COOKIE = [
    'topics-session' => '1791987166.269.16901.843849|d197bbbd1d400bd72372bc93068ad169',
    'PHPSESSID' => 'm3flhaifm6f5oitpqald4k0bs0',
    '_csrf' => 'c47fb1696f799259e346750ca2abee86e77c224d3a052cda37a4c3486824dad5a:2:{i:0;s:5:"_csrf";i:1;s:32:"Td8cH_zf4r89xHojqtXay1F3p8LKBFFL";}',
];

$_SESSION = [
    '__flash' => [],
];