The 3.8 and 3.9 failures are unrelated, see #177 for a fix.

Apple supports https://drafts.csswg.org/css-fonts-4/#ui-serif-def for this, with 'ui-serif', 'ui-sans-serif' and 'ui-monospace'. The last one allows using the system monospace font (SF Mono) without explicitly naming it.

These aren't supported by other browser at this time (according to caniuse)

Thanks, I didn't know about those! The caniuse link: https://caniuse.com/extended-system-fonts, shows 17.33% availability.

The resources tab links to the Chromium and Firefox issues, but there's not been movement for 1-2 years. Webkit (Safari) has supported it for 4 years.

The "CSS Fonts Module Level 4" spec is still draft, but was updated last month.

We could put first in font-family, and non-Safari browsers would fall back to the other fonts. But perhaps we should play safe and not use them until more browsers support it or the spec is approved? Or are they already widely used by other sites?

🚢 @hugovk Thanks!

The "CSS Fonts Module Level 4" spec is still draft, but was updated last month.

I would prefer to wait until this spec was implemented in more browsers. If we go down this route, it's worth deciding if we would prefer to be stylistically consistent based on the OS + available fonts vs aligned with the user's OS font configuration (which is likely more varied on Linux and Android compared to iOS, macOS and Windows).

I suggest we take on things from the updated font stack in a follow up, since this is a meaningful improvement over status quo!

Looks great, thanks for the PR

Thanks, I didn't know about those! The caniuse link: https://caniuse.com/extended-system-fonts, shows 17.33% availability.

The resources tab links to the Chromium and Firefox issues, but there's not been movement for 1-2 years. Webkit (Safari) has supported it for 4 years.

The "CSS Fonts Module Level 4" spec is still draft, but was updated last month.

We could put first in font-family, and non-Safari browsers would fall back to the other fonts. But perhaps we should play safe and not use them until more browsers support it or the spec is approved? Or are they already widely used by other sites?

I don't know.

I was primarily triggered by the list of fonts for "copybutton", which includes Apple's previoius preferred monospace font (Menlo), but not the current one (SF Mono). Using "ui-monospace" there would future proof us a little for Apple's platforms, although I'd assume that they'll keep using the San Francisco font suite for the foreseeable future.