Search api solr & broken views bulk operation with "Process in a batch operation"

Problem/Motivation

I'm using VBO & VBO Export & Views & Search API Solr. I set views bulk operation with option Process in a batch operation and Batch size bigger than 10. And it fails, I don't see link to download file after export.

Steps to reproduce

1. Configure Search API View with Views bulk operation setup like here:
   
   and action Generate xlsx from selected view results
2. Select more than 10 elements and export them
3. No link to download file visible after export

Proposed resolution

I found information that views without a pager are now limited to 10 results in Search API Solr (see e.g. https://www.drupal.org/project/search_api_solr/issues/3068714 🐛 Views without a pager are now limited to 10 results, make the default rows parameter configurable Fixed ). As I found here pager is disabled. So, even if we add where entity_ids IN [...] condition to query, results are limited to 10, but our batch thinks that we processed 50 elements (if we set batch size to 50 earlier).

I can set Default result rows option is Search Server settings to be equal to our batch size:



but I think better is to change here from:

$this->view->setItemsPerPage(0);

to:

$this->view->setItemsPerPage(count($batch_list));