I am not able to find the reason, but in local the copy of product which runs on 3 server produces has to be array and ID is failing to load.
So it throws ```Failed to load original object Array--entity:node/831143:en``` in web/modules/contrib/search_api_solr/src/Plugin/search_api/backend/SearchApiSolrBackend.php::extractResults() where comment line is ```// For items coming from a different site, we need to adapt the item ID.```
Just now noticed in the code, someone had same problem with different field too, copy of code from module belong (same file and func)
$item_id = $doc_fields[$id_field];
// For an unknown reason we sometimes get an array here. See
// https://www.drupal.org/project/search_api_solr/issues/3281703
if (is_array($item_id)) {
$item_id = current($item_id);
}
Active
4.2
Code
P.S. Why $id is build with 2 dashes if in DB is seems with one?
```$item_id = $doc_fields_hash . '--' . $item_id;```
seems like that was solved in ongoing 4.x already, but that is only for D10.x