Using PNG format for mermaid diagrams make the GitHub builds hang forever

[IndrajeetPatil]

Description

I have a Quarto-based revealjs presentation which renders fine both locally and in CI.

But, if I use PNG format for mermaid diagrams, the CI build hangs:
IndrajeetPatil/second-hardest-cs-thing#41

Surprisingly, I can't reproduce this behaviour locally.

Any clues on why this could be happening or how to even debug this?

[mcanouil]

The chromium-based browser installed on your runner/workflow is likely the cause.

PNG means using Puppeteer thus a browser to "take a screenshot" of the driagram, because Mermaid.js does not do PNG.

[IndrajeetPatil]

Thanks!

I can confirm that switching to macOS runner fixes the issue. It would be good to document this somewhere.

[mcanouil]

I believe you can still use a less expensive runner but need to update the browser installed (chrome I believe).