Exporting does not support the new feature Batch export:
https://www.drupal.org/project/views_data_export/issues/2789531
✨
Support for batch operations
Fixed
Closed: outdated
1.0
Code
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It's likely this issue predates Contrib.social: some issue and comment data are missing.
When I applied this patch xls_serialization-batch-export-2942178-4.patch
I am getting Fatal error in D9. that is.
Fatal error: A function with return type must return a value in xls_serialization/src/Encoder/Xls.php on line 164
I update the patch with return NULL.