- From: Boris Zbarsky <bzbarsky@mit.edu>
- Date: Thu, 30 Oct 2014 23:46:55 -0400
- To: public-web-perf@w3.org
On 10/30/14, 11:24 PM, Boris Zbarsky wrote: > I've already sent my thoughts on this to this list. I suggest just > reading those mails if you want to know what I think... But since, given my past interactions with this working group, I somewhat doubt people will do the work of looking it up, let me repeat one more time (more or less from http://lists.w3.org/Archives/Public/public-web-perf/2014Jan/0040.html and following): 1) This is a backwards-incompatible change (but see item 5 below). 2) It's a change to behavior that's been shipping for a long time now; the last time this came up was nearly a year ago, and _then_ I was concerned about content depending on the behavior and suggested that if the working group actually wants to make the behavior change it better convince implementors to make it ASAP. That clearly did not happen. 3) This change is particularly incompatible because it has knock-on effects on a number of other specifications and APIs. requestAnimationFrame is not the only API affected. 4) The behavior being suggested for requestAnimationFrame in the "Note" in the specification (I know, not normative), doesn't match any UA and I fully expect it's not web-compatible, and will assume so until proven otherwise. 5) There are no MUST requirements that result in ever returning "hidden", so as far as I can tell all existing UAs are compliant with the new spec version. Which raises the question of what the point of the change is, really. In term's of Mozilla's implementation, what I will probably be recommending internally is that we not change our behavior at all, since it's already spec-compliant and a known quantity in terms of web compat. If any other UAs do change behavior in some way, and we find out about it and think that the change is worth doing for some reason, we'll have to reverse-engineer what they're doing exactly, I guess; the spec is not particularly helpful here in terms of actually specifying behavior. -Boris
Received on Friday, 31 October 2014 03:47:23 UTC