github_document table of contents links not working for sections that begin with numbers

When I use "# 10 Section" as a section heading in a github_document with "toc: true", the href in the table of contents link is "#section", and the href in the anchor is "#10-section", so the link from the table of contents doesn't work. Is there a way I can get table of contents links to work with sections that begin with numbers?

I believe this is currently a limitation from Pandoc which is doing the conversion.
Identifier can't start with a number
From : Pandoc - Pandoc User’s Guide

  • Remove everything up to the first letter (identifiers may not begin with a number or punctuation mark).

Even for github specific extension (gfm_auto_identifier) this happens.

This would be a feature request to Pandoc that it supports for GFM keeping the starting number.
It could also be considered as a bug in Pandoc maybe because the toc produced in markdown won't work for Github.

Oh in fact it make me dig into how it works and looking at

It seems it is something that should happen at the parsing phase. So if you do this, it works as expected

title: "Test"
    md_extension: +gfm_auto_identifiers
    toc: true

# 10 Section


I think we need to fix this in github_document()

Thanks a lot for the report!

I opened an issue to track


Thank you very much for the fix and for opening the issue. The RStudio Community is such a wonderful resource!


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Thanks you very much for fixing the bug so quickly. I've installed the development version of rmarkdown, and it works perfectly.


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Thanks to you for reporting this issue !
Without your question we would not have known this was an issue. You help us improve the package and I learn from looking into your question !

Thank you very much !

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