Bug 229804

Summary: Remove (DOM Style L2) CSSValue/CSSPrimitiveValue/CSSValueList
Product: WebKit Reporter: Sam Sneddon [:gsnedders] <gsnedders>
Component: CSSAssignee: Nobody <webkit-unassigned>
Status: NEW ---    
Severity: Normal CC: koivisto, webkit-bug-importer
Priority: P2 Keywords: InRadar
Version: WebKit Local Build   
Hardware: Unspecified   
OS: Unspecified   
Bug Depends on: 229912    
Bug Blocks:    

Description Sam Sneddon [:gsnedders] 2021-09-02 06:41:43 PDT
These were never supported in IE/Edge, and were dropped in Chrome 40 (2015-01-21) and Firefox 62 (2018-09-05). As such, since 2018 we've been the only browser engine to support these.

While in some ways this has been supplanted by CSS Typed OM (see Bug 175733), Firefox nevertheless dropped support without adding support for CSS Typed OM, hence I don't think it makes sense to be the outlier and the only browser supporting these APIs.
Comment 1 Sam Sneddon [:gsnedders] 2021-09-02 08:25:25 PDT
Others have informed that some applications make use of these APIs (including via WK1), as such we're probably (at least in the short-term) limited to putting these behind a flag.
Comment 2 Radar WebKit Bug Importer 2021-09-09 06:42:16 PDT
Comment 3 Sam Sneddon [:gsnedders] 2021-12-13 06:49:21 PST
At least currently, CSSPrimitiveValue is used by fingerprint.js to detect WebKit: https://github.com/fingerprintjs/fingerprintjs/blob/09d11794dfc8da0365983bdbe638b78e2977cfd4/src/utils/browser.ts#L77