For developers

PDF++ exposes the plugin (PDFPlus) instance as the pdfPlus global variable. It has several methods to interact from the dev console:

• getPDFDocument: get the reference to PDF.js's PDFDocumentProxy object
• getPage: get the reference to PDF.js's PDFPageProxy object
• getPDFView: get Obsidian's native PDF view
• getPDFViewer: get PDFViewer instance (see typings.d.ts)
• getPDFViewerChild: get PDFViewerChild instance (see typings.d.ts)
• getObsidianViewer: get ObsidianViewer instance (see typings.d.ts)
• getRawPDFViewer: get RawPDFViewer instance (see typings.d.ts)
• getToolbar: get PDFToolbar instance (see typings.d.ts)

Tips

Get PDF.js AnnotationElement instance from a page number & an annotation ID

// in the dev console
const pageNumber = 2 // 1-based
const annotationId = '1251R' // the string you get when copying a link to the annotation
const annot = pdfPlus.getPDFViewerChild().getPage(pageNumber).annotationLayer.annotationLayer.getAnnotation(annotationId);
console.log(annot)
console.log(annot.data)

Resources

• The PDF specification.
• pdfAnnotate's README is a great resource for how PDFs work. Especially, it mentions an error in the PDF specification, which was very helpful.
• Mozilla PDF.js's recommendations: https://github.com/mozilla/pdf.js?tab=readme-ov-file#learning