public function endMobileBuffer() {
        if (!self::isMobileTheme()) {
            return;
        }
        $html = (string)ob_get_clean();
        $dropdown = $this->cartBatchDropdown('');
        $replacement = preg_replace('/<div\s+class="upbutton">.*<\/div>/', $dropdown, $html, 1);
        echo $replacement === null ? $html : $replacement;
    }