/**
* Additional validation when on a category page, so the sub category of the store root category is not added as filter.
*
* @param Mage_Catalog_Model_Category $category Category to be validated.
*
* @return bool
*/
protected function _isValidCategory($category)
{
$rootId = (int) Mage::app()->getStore()->getRootCategoryId();
if ($this->getUseUrlRewrites() && $category->getParentId() === $rootId) {
return false;
}
return parent::_isValidCategory($category);
}
