00:32
<jmdyck>
In the HTML spec, some references to "concept-fe-mutable" are via an <i> and some via a <span>. Any idea why the difference?
00:35
<annevk>
jmdyck: no, I think we'd just use <span> today.
00:37
<jmdyck>
ok thx. Shall I add a commit to that effect to #12557?
00:37
<annevk>
jmdyck: sounds good!
00:59
<jmdyck>
Done.
07:58
<smaug>
Story of interop 🙂 How did Navigation end up to interop last year. And how it got implemented twice based on broken tests and not following the spec (which was also a bit broken)
07:59
<smaug>
(But I like interop project, we just need to be more careful with the APIs being part of it)
09:11
<zcorpan>

foolip: https://html.spec.whatwg.org/#concept-media-muted when the muted state is "default" it depends on whether there's a muted content attribute. But setAttribute doesn't run "set the muted state" as far as I can tell, so per spec a muted video can be unmuted with script and continue playback?

It's not clear to me why we shouldn't honor mutations, so long as we pause videos that unmute when they shouldn't be allowed to play unmuted. I guess there's some webcompat risk with pausing instead of ignoring the muted change?

09:45
<smaug>
setting src seems to run media element load algorithm so that would happen often creation time... I guess that works. It wouldn't be too big change
10:24
<zcorpan>
smaug: there might not be a src attribute, though inserting a source element also runs media element load so maybe that works
10:24
<smaug>
sure
10:25
<zcorpan>
srcObject setter also invokes it
10:25
<smaug>
Hmm, is this racy. If parser happens to add source element in a different task
10:25
<smaug>
then one might be able to tweak muted attribute before that
10:26
<smaug>
but if source is added in the same task, then tweaking muted doesn't work
10:26
<smaug>
I mean, since tweaking muted would happen in a task after adding source
10:26
<zcorpan>
yes
11:22
<foolip>
@zcorpan:mozilla.org: are you thinking that the only time the attribute has an effect is when it's added? So that any time it's added we check if the state is "initial" and set it to true?
11:47
<zcorpan>

foolip: If there are no web compat issues I think I'd just support mutations (in the "default" state), but I don't know if this breaks content (by pausing if muted is removed).

More conservative is to "set the muted state" to true when the attribute is added. Or even only change the state if the current state is "default"

11:50
<zcorpan>
I think it's a bit surprising that .muted = value is different from removeAttribute/setAttribute
11:52
<zcorpan>
though defaultMuted exists
11:56
<foolip>
@zcorpan:mozilla.org: The most conservative would be the set of hooks that approximate the old behavior, and I think that would be just the post-connection steps. We get script insertion "for free" even though we don't really want them, but that's likely web compatible. At worst it mutes when it isn't before, less annoying than the opposite.
11:59
<foolip>
@zcorpan:mozilla.org: beyond that we could try to make the behavior for JS-created media elements sensible, and anything we do is a departure from the old spec+Chromium behavior of doing nothing.
12:00
<foolip>
@zcorpan:mozilla.org: Unmuting in response to attribute removal seems risky to me, because it might also have to pause playback, which would never happen before. That could plausibly break sites.
12:01
<zcorpan>
foolip: WebKit's behavior was different, which ought to give some leeway in terms of web compat
12:03
<zcorpan>
Getting JS-created elements behave similarly to parser-created seems good. If you use a framework that JS-creates all elements, it's surprising that the muted attribute doesn't do anything
12:32
<foolip>
@zcorpan:mozilla.org: right now I can't think of a downside to reacting to attribute mutation and go from initial/unset to true if the attr is present. Is that your ideal design too, if web compatible?
12:34
<zcorpan>
foolip: but not from false to true, right?
12:40
<foolip>
@zcorpan:mozilla.org: exactly, only the first absent->present transition could change the internal muted state (if "initial")
12:40
<zcorpan>
And avoid firing volumechange
13:49
<zcorpan>
sideshowbarker: hsivonen : is https://hsivonen.fi/last-html-quirk/ appropriate use of dl? If yes we should consider removing https://html.spec.whatwg.org/#the-dl-element:~:text=Within%20a%20single%20dl%20element%2C%20there%20should%20not%20be%20more%20than%20one%20dt%20element%20for%20each%20name