Re: Media Query Variables

Coming late to this extremely useful and interesting discussion, I have a
few points to add:
* While Kornel is right that we want picture to change its MQ evaluation
when the environment changes, we don't want it to do so *during* the page's
load. Maybe this racy behavior can be
prevented/mitigated by requiring custom MQs to be at the top of an external
CSS (possibly only the ones in the head).
* Many of the custom MQs issues already exist with @viewport. The preloader
now evaluates MQs in order to do load external stylesheets (at least in
Blink & WebKit), where @viewport can cause a preloaded stylesheet to become
irrelevant, or a non-preloaded stylesheet to become necessary. It'd be
great if we could use a single mechanism to resolve both issues.
* I don't believe authors would willfully abuse the tools we give them,
harming their site's performance. If we allow adding custom MQ/@viewport to
an external stylesheet, with a performance price tag on it, a console
warning (e.g. "You're hurting your site's performance!!! Inline that
instead.") may be enough to increase author awareness of this particular
footgun.
* Inline CSS and CSP don't mix well at the moment. CSP 1.1 has style
nonces, which are hard to deploy. Hopefully we would soon have style-hashes
(currently in discussion), which are significantly easier to use.


On Tue, Sep 17, 2013 at 10:29 AM, Andy Davies <dajdavies@gmail.com> wrote:

> On 16 September 2013 21:33, Tab Atkins Jr. <jackalmage@gmail.com> wrote:
>
>>
>> Oh good *lord* that's horrible.  document.write is *verboten*.  It's a
>> terrible, terrible API that messes everything up.
>>
>>
> Oh I know, tried explaining why is was a bad approach to someone on SO,
> only to have them delete their answer and the thread that might have been
> useful for others.
>
> DOM insertion approach also leads to undesirable behaviour in IE10 but not
> in WebKit or Mozilla
>
>