Re: Media Query Variables

On Fri, 20 Sep 2013 12:05:37 +0200, Yoav Weiss <yoav@yoav.ws> wrote:

> * 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.

This is why I think @viewport maybe was a bad idea. I can take blame for  
@viewport because, IIRC, I originally proposed it internally at Opera when  
we were implementing <meta name=viewport>, thinking "hey this seems like  
it belongs in CSS!" without considering the above issue.

> * I don't believe authors would willfully abuse the tools we give them,
> harming their site's performance.

It's not willful abuse that's the problem, it's more abuse by ignorance.  
Authors do all kinds of things that are bad for their sites' performance,  
and browser vendors bend over backwards to make it less bad. When we add  
something to the Web platform, we have to assume that it's going to be  
abused and pro-actively minimize the damage.

> 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.

It might increase awareness, sure, but certainly won't reach everyone. Why  
add support for something we don't want people to use in the first place?

> * 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.

OK. I guess <meta> doesn't have this problem.

-- 
Simon Pieters
Opera Software

Received on Friday, 20 September 2013 10:39:58 UTC