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While you wait for one of our customer support representatives to get back to you, please check out some of these documentation pages:
Guides:- Merge & extract annotation in PDF.js Express - Getting started
- Extract XFDF using the Express REST API - Response body (success)
- XFDF format - In PDF.js Express Web Viewer
- Core.Math.Rect - exportNormalize()
- ExternalAnnotationMerger - getTransformFunction()
- Core.Annotations.CustomAnnotation - new CustomAnnotation(type [, initializer])
- Merging XFDF using the Express REST API length exceeded error
- Error 504 trying to merge xfdf - Urgent
- Merging XFDF using the Express REST API using URL
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