The Font fetching requirements section of the CSS Fonts 4 spec doesn’t fully specify the requirements necessary for a UA to actually perform a font-fetch request and do something with the response.

https://drafts.csswg.org/css-fonts-4/#font-fetching-requirements

A patch (#5838) was recently merged that I wrote to add a part of the necessary requirements; but even with that change in place, there are still missing pieces:

• The spec text defines how to construct a request but should also explicitly set the request mode to cors.
• The spec doesn’t define what to do with the request; it needs to have something like, “Let response be the result of ∞fetching∞ request, where ∞fetching∞ links to the fetch algorithm in the Fetch spec.
• The spec doesn’t define what to to with the response it gets back.

@annevk