- From: litherum via GitHub <sysbot+gh@w3.org>
- Date: Fri, 21 Oct 2016 20:15:00 +0000
- To: public-css-archive@w3.org
litherum has just created a new issue for https://github.com/w3c/csswg-drafts: == [css-fonts-4] Extra unknown arguments to format() specifier should forbid font downloads/uses == When discussion the format() specifier with regards to font variations, we came across diverging behavior between different browsers. There are two possible mechanisms (that I know of) for fallback: ```css @font-face { ... src: url("file-novariations.otf") format("opentype"); src: url("file-variations.otf") format("opentype", "variations"); } ``` and ```css @font-face { ... src: url("file-variations.otf") format("opentype", "variations"), url("file-novariations.otf") format("opentype"); } ``` Currently, Edge and Firefox would download the variation font even when though the browsers don't (currently) understand variations. The spec states: > The format hint contains a comma-separated list of format strings that denote well-known font formats. Conformant user agents must skip downloading a font resource if the format hints indicate only unsupported or unknown font formats. This seems to imply that the format() identifier will be used if any of the arguments are known. Instead, in order to support modern and future font behaviors, web authors should be able to list the requirements that the browser needs to understand in order to use a font. Therefore, the format() identifier should be used if all of the arguments are known. Please view or discuss this issue at https://github.com/w3c/csswg-drafts/issues/633 using your GitHub account
Received on Friday, 21 October 2016 20:15:11 UTC