Amasty Resolution Center

[Amasty_CPS] Custom product sorting, shop by brand and catalogsearch_fulltext fail

I was unable to run catalogsearch_fulltext on our magento 2.4. getting error :
Catalog Search index exception: The attribute with a "" attributeCode doesn't exist. Verify the attribute and try again.
I find out that, even if the Amasty_ShopbyBrand is not active in BO
the Amasty_CPS code try to add the attribute used for "brand", witch doesn't exist in my case, to the list of attribute to index.
see \Amasty\CPS\Plugin\ElasticSearch\ElasticSearch5\Model\Adapter\FieldMapper\AdditionalFieldMapper::afterGetAllAttributesTypes

This code shouldn't run when 'amshopby_brand/general/attribute_code' isn't defined or when Amasty_ShopbyBrand is disabled.