Laravel.io
function get_cookie_value(string $key, $handler = null)
{
    $handler = $handler ?: app('cookie');
    $currentValue = app('request')->cookie($key);
    // if there is queued cookie - return it's value pretending like it's already present in cookies
    if ($queuedValue = $handler->queued($key)) {
        return $queuedValue->getValue();
    }

    return $currentValue;
}

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