Links and cross-references get messed up when rendering to PDF on GitHub Actions with `pdf-standard: ua-2`

I have:

• searched the issue tracker for similar issues
• installed the latest version of Quarto CLI
• formatted my issue following the Bug Reports guide

Bug description

When rendering to PDF on GitHub Actions (Ubuntu 24.04.4) with pdf-standard: ua-2, my links and cross-references get messed up in Quarto version 1.10.18.

For example, [URL link](https://www.google.com) gets converted to 0.0 0.0 1.00 g 0 GURL link.

I only experience this issue on GitHubActions. I do not experience it locally.

Steps to reproduce

Here is a link to a GitHub repo with a minimal reproducible example: https://github.com/isaactpetersen/quartoReprex2

Here are the contents of index.pdf:

---
title: "Quarto Reprex"
---

This is a [cross-reference link](syllabus.qmd).

This is a [URL link](https://www.google.com).

This renders as:

Quarto Reprex
This is a 0.0 0.0 1.00 g 0 Gcross-reference link.
This is a 0.0 0.0 1.00 g 0 GURL link.

Here are the contents of syllabus.qmd:

---
title: "Syllabus"
---

This is a [cross-reference link](index.qmd).

This is a [URL link](https://www.google.com).

Here are the contents of _quarto.yml:

project:
  type: website

website:
  title: "Quarto Reprex"
  repo-url: https://github.com/isaactpetersen/quartoReprex2

format:
  html:
    toc: true
  pdf:
    toc: false
    pdf-standard: ua-2 # links and cross-references work fine when I comment out this line

Here are the contents of the DESCRIPTION file:

Package: placeholder
Title: QuartoReprex
Version: 1.0.0
Imports:
  quarto,
  knitr,
  rmarkdown

Here are the contents of .github/workflows/publish.yml:

on:
    workflow_dispatch:
    push:
       branches:
         - main

name: Quarto Publish

jobs:
  build-deploy:
    runs-on: ubuntu-latest
    permissions:
      contents: write
    steps:
      - name: Check out repository
        uses: actions/checkout@v6
    
      - name: Set up Quarto
        uses: quarto-dev/quarto-actions/setup@v2
    
      - name: Install R
        uses: r-lib/actions/setup-r@v2
    
      - name: Session info
        run: Rscript -e 'sessionInfo()'
    
      - name: Setup pandoc
        uses: r-lib/actions/setup-pandoc@v2
    
      - name: Install system dependencies
        if: runner.os == 'Linux'
        run: |
          sudo apt-get update -y
          sudo apt-get install -y \
            libcurl4-openssl-dev \
            libharfbuzz-dev \
            libfribidi-dev

      - name: Install veraPDF for accessibility validation
        run: quarto install verapdf
        
      - name: Install tinytex
        uses: r-lib/actions/setup-tinytex@v2
        
      - name: Install additional LaTeX packages
        run: |
          tlmgr update --self
          tlmgr install \
            collectbox \
            titling \
            framed \
            mdframed \
            ulem \
            hyperref \
            url \
            underscore \
            xcolor \
            csquotes
    
      - name: Install package dependencies
        uses: r-lib/actions/setup-r-dependencies@v2

      - name: Render & Publish
        uses: quarto-dev/quarto-actions/publish@v2
        with:
          target: gh-pages

      - name: List files in workspace
        if: always()
        run: |
          ls -lh
          find . -type f
          
      - name: Archive production artifacts
        if: always()
        uses: actions/upload-artifact@v7
        with:
          name: site
          path: _site/

Here is a link to the rendered PDF: https://isaactpetersen.github.io/quartoReprex2/index.pdf

Actual behavior

Links and cross-references get converted to: 0.0 0.0 1.00 g 0 G

Expected behavior

I expected the URL links and cross-reference links to show correctly.

Your environment

• OS: Ubuntu 24.04.4 via GitHub Actions
• Quarto: version 1.10.18

Quarto check output

  quarto check
  shell: /usr/bin/bash -e {0}
  env:
    BUNDLE_EXT: linux-amd64.deb
    R_LIBS_USER: /home/runner/work/_temp/Library
    TZ: UTC
    _R_CHECK_SYSTEM_CLOCK_: FALSE
    NOT_CRAN: true
    RSPM: https://packagemanager.posit.co/cran/__linux__/noble/latest
    RENV_CONFIG_REPOS_OVERRIDE: https://packagemanager.posit.co/cran/__linux__/noble/latest
    R_LIB_FOR_PAK: /opt/R/4.6.1/lib/R/site-library
  
Quarto 1.10.18
[✓] Checking environment information...
      Quarto cache location: /home/runner/.cache/quarto
[✓] Checking versions of quarto binary dependencies...
      Pandoc version 3.10.0: OK
      Dart Sass version 1.101.0: OK
      Deno version 2.7.14: OK
      Typst version 0.15.1: OK
[✓] Checking versions of quarto dependencies......OK
[✓] Checking Quarto installation......OK
      Version: 1.10.18
      Path: /opt/quarto/bin

[✓] Checking tools....................OK
      TinyTeX: (external install)
      VeraPDF: 1.28.2
      Chrome Headless Shell: (not installed)
(|) Checking LaTeX....................
[✓] Checking LaTeX....................OK
      Using: TinyTex
      Path: /home/runner/.TinyTeX/bin/x86_64-linux
      Version: 2026

[✓] Checking Chrome Headless....................OK
      Using: Chrome found on system
      Path: /usr/bin/google-chrome
      Source: PATH
(|) Checking basic markdown render....
[✓] Checking basic markdown render....OK
(|) Checking R installation...........
[✓] Checking R installation...........OK
      Version: 4.6.1
      Path: /opt/R/4.6.1/lib/R
      LibPaths:
        - /home/runner/work/_temp/Library
        - /opt/R/4.6.1/lib/R/site-library
        - /opt/R/4.6.1/lib/R/library
      knitr: 1.51
      rmarkdown: 2.31
(|) Checking Knitr engine render......
[✓] Checking Knitr engine render......OK
(|) Checking Python 3 installation....
[✓] Checking Python 3 installation....OK
      Version: 3.12.3
      Path: /usr/bin/python3
      Jupyter: (None)
      Jupyter is not available in this Python installation.
      Install with python3 -m pip install jupyter
(|) Checking Julia installation...
[✓] Checking Julia installation...

Start with the minimal repository, especially _quarto.yml, index.qmd, syllabus.qmd, and .github/workflows/publish.yml, then compare local and GitHub Actions PDF rendering with pdf-standard: ua-2. Check the generated index.pdf and the listed Quarto, TinyTeX, and workflow environment details. Done means URL links and cross-references render as readable links in the Actions-produced PDF.