Repo actions in book proj not visible in mobile view

[blacksqr]

Bug description

In a book project with repo actions defined, if a chapter has a TOC, the repo action icon will not appear in the footer if the page is displayed in mobile view.

Chapters without a TOC will display the icon as expected.

Steps to reproduce

Create a book project:

$ quarto create-project mybook --type book
$ quarto preview mybook

Edit _quarto.yml so it appears as follows:

project:
  type: book

book:
  title: "mybook"
  author: "Norah Jones"
  date: "6/5/2023"
  repo-url: "https://github.com/quarto-dev/quarto-web/"
  repo-actions: [source]
  chapters:
    - index.qmd
    - intro.qmd
    - summary.qmd
    - references.qmd

bibliography: references.bib

format:
  html:
    theme: cosmo
  pdf:
    documentclass: scrreprt

When the project re-renders and I navigate the the Preface page, the github "View Source" icon is visible in the TOC.

Switch to mobile view in the newly rendered project (ctrl-shift-m for Firefox)

Expected behavior

On the Preface page, I expect to see the github icon with "View Source" label in the footer when in mobile view.

Actual behavior

The github icon on the Preface page is missing. It appears in the footer on all the other chapter pages in mobile view, because they don't have a TOC.

Your environment

• Quarto version 1.4.122
• OS: Kubuntu 20.04

Quarto check output

[✓] Checking versions of quarto binary dependencies...
      Pandoc version 3.1.2: OK
      Dart Sass version 1.55.0: OK
      Deno version 1.33.2: OK
[✓] Checking versions of quarto dependencies......OK
[✓] Checking Quarto installation......OK
      Version: 1.4.122
      Path: /opt/quarto/bin

[✓] Checking basic markdown render....OK

[✓] Checking Python 3 installation....OK
      Version: 3.8.10
      Path: /usr/bin/python3
      Jupyter: (None)

      Jupyter is not available in this Python installation.
      Install with python3 -m pip install jupyter

      There is an unactivated Python environment in systemd-private-90e163f7653b4f69ae913301b284ec8a-systemd-resolved.service-YMBMlh. Did you forget to activate it?

[✓] Checking R installation...........OK
      Version: 4.2.1
      Path: /usr/lib/R
      LibPaths:
        - /usr/local/lib/R/site-library
        - /usr/lib/R/site-library
        - /usr/lib/R/library
      knitr: 1.37
      rmarkdown: 2.11

[✓] Checking Knitr engine render......OK

[mcanouil]

Thank you for the report!
Could you additionally add some screenshots to ensure we understand this right?

[blacksqr]

Preface page. No github icon in footer:

Introduction page. Github icon in footer: