Re: Sharing MathML data for Firefox

On 22/08/2019 20:01, Hammond, William F wrote:
> I assume this is about MathML elements such as "mfenced" that
> previously you have expressed a wish to drop.  I continue to advise
> you not to take any such step.

From spec authors' point of view: the MathML CG already decided to
remove mfenced and other features from MathML Core. They will stay in
MathML full but won't have web platform tests for them and the
expectation is that they are implemented via JS polyfill.

From implementers' point of view: the plan is to try and unship these
features. However, this will be done carefully by measuring & analyzing
data and adding runtime flag.

> That said, I have questions:
>
> Will your probe pick up instances where MathJax ("CommonHTML")
> rendering of MathML is used?
>
> Will your probe pick up instances served as "application/xhtml+xml"? 
> I mention this case because some web searching algorithms seem often
> to have bypassed it.

The probe will only measure MathML content that is actually rendered by
Firefox. Being in the DOM is not enough, for example by default
Wikipedia has MathML content with "display: none" so it is excluded from
the data. The fact of being handled by the HTML5 or XHTML parser does
not matter here. One can use
https://addons.mozilla.org/en-US/firefox/addon/native-mathml or similar
to force native MathML rendering.

To play devil's advocate, if MathML or some of its features are actually
not rendered in browsers then it makes sense for browser vendors to
actually remove them. So measuring MathML content that is actually
rendered by browsers is the correct measurement from that point of view.

There are discussions in the MathML CG to collect more data besides
native implementation but unfortunately we didn't get a lot of feedback
on this so far.

Note: I'm not going to give more details here, discussion is already
taking place in the proper channels.

Thanks,

-- 
Frédéric Wang