PDF/UA-2 accessibility enhancement - Tagged pdf support via recent updates to LaTeX2e, LuaLaTeX, pdfLaTeX

[paytonej]

Description

As of 2025-11-01, LaTeX2e using the LuaLaTeX and pdfLaTeX engines supports automatic tagging to meet ISO 14289-2 PDF/UA-2 standards. This is accomplished primarily through a new \DocumentMetadata{...} declaration before \DocumentClass{...}. Usage instructions for the tagging support can be found at https://latex3.github.io/tagging-project/documentation/usage-instructions.

This should be a high-priority feature request in particular due to new rules taking effect in April 2026 under Title II of the Americans with Disabilities Act and the requirements of the European Accessibility Act (EAA), which went into effect in June 2025. The current LaTeX-based pdf outputs from Quarto are not compliant. Enhancing Quarto to use the new tagging capabilities in the default LuaLaTeX engine would, however, benefit all users.

Perhaps the pdf accessibility enhancement could be as simple as adding a "DocumentMetadata" partial to the src/resources/formats/pdf/pandoc directory and then updating src/resources/formats/pdf/pandoc/doc-class.tex to pull in this partial?

If so, this "DocumentMetadata" partial might look something like:

\DocumentMetadata{
  lang = en,
  pdfstandard = ua-2,
  pdfstandard = a-4f, %or a-4
  tagging=on,
  tagging-setup={math/setup=mathml-SE} 
}

with the lang variable being set by Quarto yaml.

Related older requests that predate the November 2025 update to LaTeX2e:

• https://github.com/orgs/quarto-dev/discussions/11116
• https://github.com/orgs/quarto-dev/discussions/9333
• https://github.com/orgs/quarto-dev/discussions/5669

[mcanouil]

@paytonej please properly set a meaningful title. Thank you!

[paytonej]

@mcanouil sorry I neglected to enter something in that field! Fixed now.