[css-2025][css-will-change-1] Add CSS Will Change 1 to Reliable CRs

[SebastianZ]

Splitting the discussion from #9770 for adding CSS Will Change 1 to the Reliable Candidate Recommendations section of the CSS Snapshot 2025.

Data to consider:

Current status: CRD (last published: 5 May 2022), ED from 29 April 2022
WPT: passing tests (stable): Chrome: 169, Edge: 169, Firefox: 174, Safari: 166; interop: 161 / 175 (92.0%), 168 / 175 (96.0%) for Chrome, Edge, and Firefox
Current Snapshot section: Rough Interoperability
Open issues: on GitHub: 12 (~8 substantial), in spec.: 0

Summary: Very high interoperability, spec. in CRD, some open issues

Sebastian

[css-meeting-bot]

The CSS Working Group just discussed [css-2025][css-will-change-1] Add CSS Will Change 1 to Reliable CRs.

The full IRC log of that discussion

<emeyer> SebastianZ: will-change has very high interop in main engines; 12 open issues, with 8 substantial, zero open issues in the spec
<emeyer> …propose to move to Reliable CR
<emeyer> florian: I suspect that’s possiblke but I’m concerned that it’s under-maintained because it hasn’t been looked at in a while
<emeyer> …We haven’t been actively thinking about the open issues
<emeyer> …Would like assurance from someone who’s worked on this more directly
<emeyer> astearns: I’m concerned about the number of issues, but not having looked at them, I don’t konw if they’re for the next level or not
<emeyer> florian: Skimming, some seem like interop, but there might be de facto interop
<emeyer> …We could probably get there, but not having looked at the spec in three years, I don’t know how much effort it would take to find out
<emeyer> astearns: Shall we close no change?
<emeyer> florian: Can we punt and come back when Tab can give input?
<TabAtkins> Note: I cannot answer those questions right now, it's been a few years since I've had to work on it.
<emeyer> …The ED is as old as the TR draft
<emeyer> astearns: Let’s take no resolution and come back to it
<ChrisL> q+ to wonder who the real editors of MQ5 are
<emeyer> SebastianZ: That works for me