Bug 187117

Summary: Forwards-compatible parsing of @font-face src descriptor: split on commas, discard invalid parts rather than entire descriptor
Product: WebKit Reporter: fantasai <fantasai.bugs>
Component: CSSAssignee: Myles C. Maxfield <mmaxfield>
Status: NEW ---    
Severity: Normal CC: emilio, mmaxfield
Priority: P2    
Version: WebKit Nightly Build   
Hardware: Unspecified   
OS: Unspecified   
Attachments:
Description Flags
testcase (requires Ahem) none

Description fantasai 2018-06-27 15:03:46 PDT
Created attachment 343755 [details]
testcase (requires Ahem)

In light of discussions for extending the format() descriptor to handle features (e.g. colors, variations) within a particular font format, the CSSWG recently resolved to update the parsing rules for @font-face's src descriptor to be more forwards-compatible, using Media Queries style parsing rules to split on top-level commas, and discard only the invalid items in the src list rather than throwing out the entire descriptor.

https://github.com/w3c/csswg-drafts/issues/633

I think this is an important change to implement even before the new features are implemented, as it means WebKit will be forwards-compatible with content authored using new format() features, whatever they end up being.