Funny business

## Firefox 38 with respimg support ships *tomorrow*

It’ll support everything (`srcset`, `x`, `w`, `sizes`, `picture`, 
`type`, and `media`) but doesn’t respond to viewport changes — yet. 
Those should arrive 
[shortly](https://bugzilla.mozilla.org/show_bug.cgi?id=1135812#c32).

Speaking of major implementation news…

## `w` and `sizes` have landed in WebKit nightlies

`srcset` and `x` descriptors have been shipping in WebKit [since  
forever](https://www.webkit.org/blog/2910/improved-support-for-high-resolution-displays-with-the-srcset-image-attribute/), 
and while support for `w` descriptors and `sizes` [came in 
June](https://bugs.webkit.org/show_bug.cgi?id=133620), that support has 
been hidden behind a compile-time flag. That changed last week. Yoav – 
after [a Twitter 
exchange](https://twitter.com/awfulben/status/595852748375068672) with 
WebKit engineer Benjamin Poulain – 
[fixed](https://bugs.webkit.org/show_bug.cgi?id=144766) 
[a](https://bugs.webkit.org/show_bug.cgi?id=144640) 
[few](https://bugs.webkit.org/show_bug.cgi?id=144739) 
[bugs](https://bugs.webkit.org/show_bug.cgi?id=144675), [added a 
boatload of tests](https://bugs.webkit.org/show_bug.cgi?id=144674), 
[removed a compile time 
flag](https://bugs.webkit.org/show_bug.cgi?id=144679) *et voilà* – 
WebKit nightly now has full `srcset` and `sizes` support as part of the 
main codebase.

Yoav’s tests are good, but testing against real-world production-code 
is better, so [download WebKit Nightly](http://nightly.webkit.org/), 
point it to your `srcset`s, and [let Yoav 
know](https://twitter.com/yoavweiss) about any funny business.


## Picturefill 3 
[comin’](https://github.com/scottjehl/picturefill/issues/492)

It will be both faster (especially on sites with huge numbers of images 
and/or complex DOMs) and more furious, where by “furious” I of 
course mean “spec- and test-compliant, mimicking as much native 
behavior as is possible”. For example: just like Chrome, if the 
polyfill finds a larger image than it needs from a given `srcset` 
available in the cache, it’ll use that, rather than downloading an 
entirely new, smaller image.

Oh, and the docs page should be getting [a spiffy new 
re-design](https://github.com/scottjehl/picturefill/issues/495).

## Grab bag

- Want respimg in the WordPress core? [Get involved in the 
effort!](https://twitter.com/kadamwhite/status/596707141135695873) (more 
detailed instructions on joining the WordPress Slack are 
[here](https://make.wordpress.org/chat/).

- Dave Newton speaks! Dave Newton [will 
speak!](https://2015.cssconf.com/#speakers) (at the CSSConf in New York 
on June 18th and 19th) Dave Newton 
[has](https://speakerdeck.com/newtron/universal-web-design-how-to-create-an-awesome-experience-for-every-user-openwest) 
[spoken!](https://speakerdeck.com/newtron/improving-performance-with-responsive-and-responsible-images-openwest) 
(on respimg and the broader goal of a universally accessible web at the 
OpenWest conference in Provo, Utah)

- I penned a tiny update to my A List Apart respimg article, talking 
about how and why my examples no longer validate. [Don’t rely on 
default 
`sizes`](http://alistapart.com/blog/post/article-update-dont-rely-on-default-sizes/)!

- Here’s a nice little implementation experience writeup: stuff.co.nz 
[wrote up their 
struggle](https://technology.fairfaxmedia.co.nz/responsive-images-using-srcset/) 
with an age-old Picturefill question: whether or not to include a `src`. 
The prose leads me to believe that after trying to cheat fate with some 
ill-advised `visibility: hidden;` and `<noscript>` trickery, they came 
down on the side of including a `src` and risking double downloads (even 
though `src` is missing from the last example).

- Yoav [took to his blog](http://blog.yoav.ws/long_overdue/) to 
summarize the last eventful, productive, and respimg-filled year and a 
half of his life. The best part: promises of more blogging!

See you in a couple of weeks!

—eric