Magento 2 invalid Form key

There is also in Magento 2 a form key validator

Magento\Framework\Data\Form\FormKey\Validator

 public function validate(\Magento\Framework\App\RequestInterface $request)
    {
        $formKey = $request->getParam('form_key', null);
        if (!$formKey || $formKey !== $this->_formKey->getFormKey()) {
            return false;//for solving please return true here
        }
        return true;
    }