Quarto book with brand.yml and a favicon: should it work only with the image specified as small in the branding file?

[novica]

Description

I am trying to do a demo of a quarto book that uses brand.yml. As I understand the documentation at https://posit-dev.github.io/brand-yml/brand/logo.html using the small attribute should provide the branding with a image to use for a favicon. However, rendering the default demo project with a brand.yml that has

logo:
  small: logo/favicon.png

and quarto.yml

format:
  html:
    theme:
      - brand

Does not show a favicon at the end of rendering.

Adding:

  favicon: brand/logo/favicon.png

To the book: section of the quarto.yml displays the favicon.

I am wondering if this is expected behavior, a bug, or maybe I am doing something wrong.

Running Quarto 1.6.42, R 4.3.1, Rstudio 2025.05.0 on Windows 11.

[mcanouil]

Upgrade to 1.7.