What does the call to "https://pi.pdfjs.express/events" means?

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Hello, I’m Ron, an automated tech support bot

While you wait for one of our customer support representatives to get back to you, please check out some of these documentation pages:

Guides:

• Set up measurement tools
• PDF.js Express annotations - Get started
• Framework compatibility for PDF.js Express - Call APIs

APIs:

• Core - enableFullPDF()
• PDF.js Express Utilities
• Core.Annotations - setCustomSerializeHandler(annotationClass, serializeHandler)

Forums:

• Do annotations from setCustomDrawHandler make it to the downloadable file?
• Importing XFDF has failed
• Get coordinates of X and Y of the signature image