private function setFormName() : void
    {
        $this->key = 'form_' . $this->name . '_' . bin2hex(random_bytes(16));

        // Form key must be unique
        if (isset($_SESSION[$this->key])) {
            $this->setFormName();
        }

        // Remove potential previous form with same name from session
        $prev_form_keys = preg_grep('/^form_' . preg_quote($this->name, '/') . '_[a-f0-9]+$/', array_keys($_SESSION));
        array_map(function ($key) {
            unset($_SESSION[$key]);
        }, $prev_form_keys);

        // Save the new form
        $_SESSION[$this->key] = [];
    }