### Bug description

From default website template created with `quarto create`, editing `about.qmd` to include a `revealjs` format along with `output-file`:

```
---
title: "About"
format:
  html: default
  revealjs: 
    output-file: about-reveal.html
---
```

Then running:
```
quarto render
```

In `_site/about.html` line 104, the link to the Revealjs slides is relative to my Home directory not the site directory:
```html
<a href="/Users/wickhamc/Documents/posit/multi-format/website-pdf-reveal/about-reveal.html"><i class="bi bi-file-slides"></i>RevealJS</a>
```

This doesn't seem to be a problem with standalone HTML documents.

Mac OS, dev Quarto, RStudio Version 2023.03.0-daily+302 (2023.03.0-daily+302)

### Checklist

- [X] Please include a minimal, fully reproducible example in a single .qmd file? Please provide the whole file rather than the snippet you believe is causing the issue.
- [X] Please [format your issue](https://quarto.org/bug-reports.html#formatting-make-githubs-markdown-work-for-us) so it is easier for us to read the bug report.
- [X] Please document the RStudio IDE version you're running (if applicable), by providing the value displayed in the "About RStudio" main menu dialog?
- [X] Please document the operating system you're running. If on Linux, please provide the specific distribution.
2023-02-24T22:36:06Z
cwickham
bug
closed
Malformed Links in Multi-format when `output-file` is provided
https://github.com/quarto-dev/quarto-cli/issues/4526