Support opening PDFs with #page=<pageNumber>

[Wombosvideo]

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Pre-checks*

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• The feature request has not been suggested in this repository.

The Missed*

Is your feature request related to a problem? Please provide a clear and concise description of what the problem is.

• Links to PDF files, i.e. in markdown files or the markdown preview do not support the page hash for directly linking to a specific page
• The broadly suggested PDF extension vscode-pdf is not actively maintained

The Solution*

Please provide a solution you would like to have.

• Be able to open links to specific pages using filename.pdf#page=<pageNumber>

Anything Else?

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• Adobe's "Specification" of the feature: Create a URL to open a PDF file at a specific page
• Microsoft Community: Commanding a pdf to open at a specific page by altering URL
• Closed issue at pdf.js: Expose fragment IDs in the URL mozilla/pdf.js#5258 (comment)
• Open issues at vscode-pdf:
  • open PDFs on a specific page by Markdown-Link tomoki1207/vscode-pdfviewer#108
  • Open specific pdf page via markdown link tomoki1207/vscode-pdfviewer#129
  • Feature Request - support links to pages and sections tomoki1207/vscode-pdfviewer#166

[James-Yu]

It's not possible without some fundamental changes at vscode. From the extension perspective, we receive a vscode.Uri passed to resolveCustomEditor in class vscode.CustomReadonlyEditorProvider. However, in the URI, no hash information is provided. It means that the extension has no way to know if the clicked link has a hash component or not.

I don't think it is an easy change on the vscode side. However, there is no easy or hard or dirty workaround to obtain the hash string otherwise.