Subject: [Justfont] Where are @font-face format identifiers defined?

From: "Chris Lilley" <[email-masked]>
Date: Thu, 08 Dec 2016 17:55:14 -0500

There is an open issue on "Where are @font-face format identifiers defined?"

When the issue was first opened, I was of the opinion that the source of truth should be individual media type registrations. CSS3 Fonts would then informatively list the current format identifiers.

Two things have changed my mind on this issue.

Firstly, not every use of font media types will be with CSS. For example, an online emulator for a game console might use a console-specific font format and might well register a media type for it. There is no good reason that font/snes should have to specify a CSS Fonts format identifier.

Secondly, the use of format strings in CSS is being extended in CSS 4 Fonts, to cope with OpenType 1.8 variable fonts. There are various proposals, some of which directly change the format identifier and some do not.
There is no consensus on the issue at this time.
https://github.com/w3c/csswg-drafts/issues/633

it therefore seems risky to make the font top level draft specify them normatively.

The other option, as suggested by the original review comment, is to clearly state that the CSS specification is normative and not require new registrations to specify them.

As Wendy mentioned, there is no obvious downside to this, no-one is disadvantaged and it makes things faster. Comments?

--
Chris Lilley
@svgeesus
Technical Director @ W3C
W3C Strategy Team, Core Web Design
W3C Architecture & Technology Team, Core Web & Media