SELECT 
  cscart_product_filters.filter_id 
FROM 
  cscart_product_features_values 
  LEFT JOIN cscart_products as products ON products.product_id = cscart_product_features_values.product_id 
  LEFT JOIN cscart_product_filters ON cscart_product_filters.feature_id = cscart_product_features_values.feature_id 
  LEFT JOIN cscart_product_features ON cscart_product_features.feature_id = cscart_product_features_values.feature_id 
  INNER JOIN cscart_products_categories as products_categories ON products_categories.product_id = products.product_id 
  INNER JOIN cscart_categories ON cscart_categories.category_id = products_categories.category_id 
  AND (
    cscart_categories.usergroup_ids = '' 
    OR FIND_IN_SET(
      0, cscart_categories.usergroup_ids
    ) 
    OR FIND_IN_SET(
      1, cscart_categories.usergroup_ids
    )
  ) 
  AND cscart_categories.status IN ('A', 'H') 
  LEFT JOIN cscart_ult_product_descriptions shared_descr ON products.product_id = shared_descr.product_id 
  LEFT JOIN cscart_aval_statuses ON cscart_aval_statuses.aval_status_id = products.aval_status 
  LEFT JOIN cscart_aval_statuses_descr ON cscart_aval_statuses.aval_status_id = cscart_aval_statuses_descr.aval_status_id 
  AND cscart_aval_statuses.status = 'A' 
  AND cscart_aval_statuses_descr.lang_code = 'se' 
  LEFT JOIN cscart_product_popularity as popularity ON popularity.product_id = products.product_id 
WHERE 
  cscart_product_filters.filter_id IN (13) 
  AND cscart_product_features_values.feature_id IN (30) 
  AND cscart_product_features_values.value = 'Y' 
  AND cscart_product_features_values.lang_code = 'se' 
  AND cscart_categories.category_id IN (952) 
  AND cscart_categories.company_id = 2 
  AND (
    products.usergroup_ids = '' 
    OR FIND_IN_SET(0, products.usergroup_ids) 
    OR FIND_IN_SET(1, products.usergroup_ids)
  ) 
  AND products.status IN ('A') 
  AND cscart_product_features.feature_type = 'C' 
GROUP BY 
  cscart_product_features_values.feature_id

Query time 0.00054

Explain
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE Impossible WHERE noticed after reading const tables