https://github.com/miguelpruivo/flutter_file_picker/issues/1743 here you have the problem with that bug and his resolution, if you in your code sets the compressionQuality: 0, it works succesfully without duplicate images:

FilePickerResult? result = await FilePicker.platform.pickFiles(
      allowMultiple: true,
      type: FileType.image,
      compressionQuality: 0
      
    );