Hyperlink to external website from book sidebar

Hi there, Quarto team!

When working in a Quarto book, is it possible right now to have a "chapter" hyperlink to a different website? Specifically, I'm thinking about how Bookdown uses specific code in the bookdown::gitbook: section of the _output.yml file (code linked) to create the "View book source" link on the Tidy Text Mining site.

I'm trying to convert my team's training manual from a bookdown to a quarto book, and I've been racking my brain trying to figure this out to link to our extra reference manual from the main training document. I feel like I keep just barely skirting around the solution, but I just can't seem to put things together 😅 I know I can get creative and just make the document a website rather than a book and get things to work that way, but I'm curious if there's a current way to make this work from a book, specifically.

Apologies if this already been asked, I've perused all the discussions and issues, but still could have missed it! Thanks!

Start by reviewing the linked _output.yml example and the bookdown::gitbook configuration mentioned in the issue. Compare how the “View book source” link is represented there with Quarto book sidebar behavior. Done means determining and documenting whether a Quarto book can expose a chapter-like link to an external website, or identifying the required feature scope.