XML parser ignores the data-fetcher plugin

This works great, thanks for the patch. Setting to needs work to inject the FileSystem service rather than accessing it through the `\Drupal::service()` facade.

Injected the FileSystem service and rerolled for 6.0.x.

Patch resolves the issue

Thanks for the contributions.

Automatically closed - issue fixed for 2 weeks with no activity.

Unfortunately, this caused a regression for me that I just noticed, because those temporary files used up almost all disk space on the server by now for a regular import using migrate. See 🐛 [Regression] Clean up temporary files created by XML data parser plugin Active .