Internal Server 500

Which product are you using?
-=PDF.js Express Plus

PDF.js Express Version

Detailed description of issue
Receiving 500 server error when using the merge API.

Does your issue happen with every document, or just one?
Every document.

Link to document
Documents are internal.

Code snippet
const xfdf = await annotManager.exportAnnotations({
links: false,
widgets: false
const fileData = await docViewer.getDocument().getFileData({});
const blob = new Blob([fileData], {
type: ‘application/pdf’

                const data = new FormData();
                data.append('xfdf', xfdf);
                data.append('file', blob);
                data.append('license', 'USING_THE_PROVIDED_CLIENT_API_KEY');

                // Process the file
                const response = await fetch('', {
                    method: 'post',
                    body: data
                }).then(resp => resp.json());

                const {
                } = response;

                // Download the file
                const mergedFileBlob = await fetch(url, {
                    headers: {
                        Authorization: key
                }).then(resp => resp.blob())

Thank you for posting the incident to our forum. We will provide you with an update as soon as possible.

Hello hbichri,

Can you provide the document + some example XFDF to test out?

Best regards,