Question, about XFDF that I see for the first time

Product:
Product Version:

"@pdftron/webviewer": "^10.1.0",
"@pdftron/webviewer-video": "^4.34.0",

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Question, about XFDF that I see for the first time
About XFDF without ‘’

Please describe your issue and provide steps to reproduce it:
(The more descriptive your answer, the faster we are able to help you)
The procedure is unknown.

Convert Anotation to XFDF and save to DB.
(exportAnnotations: Apryse Documentation | Documentation)
One day, the following XFDF occurred and became a problem.

‘<?xml version=\"1.0\" encoding=\"UTF-8\" ?><xfdf xmlns="http://ns.adobe.com/xfdf/\" xml:space="preserve">’

Please let me know the steps by which this happens.

Please provide a link to a minimal sample where the issue is reproducible:

Best Regards.

Hello Okabe,

I don’t understand the issue. Is the xfdf you posted causing a problem? Are there errors present in the console. The xfdf you posted has no annotations, so it should not do anything when you import it.

Best regards,
Kristian

Hello, Kristian.

I am developing like this.
(sample)

private xfdfs: string[] = [];

WebViewer({license,,,etc,,}).then(instance: WebViewerInstance) => {
  instance.Core.annotationManager.addEventListener(
    'annotationChanged', () => {
    const xfdfString =
      await this.viewerInstance.Core.annotationManager.exportAnnotations();
    this.xfdfs.push(xfdf);
  });

  instance.Core.documentViewer.addEventListener('documentLoaded', () => {
    const xfdfs: string[] = Database.getXfdfs();
    xfdfs.foreach(xfdf => {
      instancce.Core.annotationManager
        .importAnnotations(xfdf)
        .then((annotations) => {
                instance.Core.annotationManager.redrawAnnotation(
                  annotations[0] 
                );
         });
    });
  });
});

onClickAnnotationSaveButton = () => {
    Database.save(this.xfdfs);
}

This xfdf is importAnnotations return null;

<?xml version=\"1.0\" encoding=\"UTF-8\" ?><xfdf xmlns="[http://ns.adobe.com/xfdf/\](http://ns.adobe.com/xfdf/%5C)" xml:space="preserve">’

Therefore, redrawAnnotation Error.

I got around it by using a null check.

However, I do not know under what conditions this xfdf is created in the first place.

Best regards.