Tredning up

# Trending up

## Put to work

All of this new markup that I prattle on about – how big of a deal is 
it, really? It has been a while since we last checked in with 
Chromium’s usage stats; so let’s (click the links for historical 
charts):

- [`w` 
descriptors](https://www.chromestatus.com/metrics/feature/timeline/popularity/524) 
and 
[`sizes`](https://www.chromestatus.com/metrics/feature/timeline/popularity/522) 
are both employed in one out of every 5,000 Chromium page loads.
- 
[`picture`](https://www.chromestatus.com/metrics/feature/timeline/popularity/521): 
1 in 2,000
- [`x` 
descriptors](https://www.chromestatus.com/metrics/feature/timeline/popularity/523): 
1 in 300

These charts raise interesting questions. Why is usage for all of these 
features up on the weekends and down during the work-week? Why has `x` 
descriptor usage fallen off slightly, after its meteoric rise? Most 
[recent](https://css-tricks.com/responsive-images-youre-just-changing-resolutions-use-srcset/) 
[articles](http://blog.cloudfour.com/dont-use-picture-most-of-the-time/) 
on the topic explicitly recommend using `srcset` + `w` descriptors for 
the most common case: images in flexible layouts that need to scale 
across both viewport sizes and screen resolutions. But that markup is 
currently dead last in the usage derby. Will it catch up?

One interesting thing to note: `sizes` caught up with `w` descriptors 
*fast*, right after it was [made 
mandatory](https://github.com/ResponsiveImagesCG/picture-element/commit/535e96b73ea8b0e94a7819b1482cd48bff18698e), 
despite the fact that browsers handle `sizes`-less markup the same way 
that they always did. Three cheers for making changes without breaking 
pages!

## Container queries have a home

“Container queries,” née “Element queries,” now have [a spec 
URL](http://responsiveimagescg.github.io/container-queries/). There’s 
little more than an abstract and some good intentions there at the 
moment, but from such humble beginnings, great things are born.

## PSA: upgrade your Picturefills

The [Picturefill 2.3.1 
update](http://scottjehl.github.io/picturefill/#download) that I 
mentioned last week – which provided support for the Spartan developer 
preview – fixes more than just Spartan. Due to the way that the plugin 
used to feature-test, Picturefills ≤ 2.3.0 throw errors on WebKit 
Nightly, too. Which presumably means that those old Picturefills will 
cause errors in Mobile/Safari in the near future. So, 
[upgrade](http://scottjehl.github.io/picturefill/#download)!

## Grab Bag

- Yoav has formally expressed an [intent-to-implement Client Hints in 
WebKit](https://lists.webkit.org/pipermail/webkit-dev/2015-April/027381.html). 
I’d be more worried about the [stiff 
initial](https://lists.webkit.org/pipermail/webkit-dev/2015-April/027382.html) 
[resistance](https://lists.webkit.org/pipermail/webkit-dev/2015-April/027383.html) 
if that sort of response hadn’t characterized literally everything 
that Yoav has managed to do for the RICG over the last couple of years.
- Dan Matthew [wrote up his respimg implementation 
experiences](http://www.danmatthew.co.uk/2015/04/19/implementing-responsive-images/). 
The performance gains that he details (3.4 MB → 522 Kb) are 
particularly huge due to Dan’s simultaneous switch to lossy image 
compression (using JPEGs instead of PNGs for screenshots), but still! A 
thousand more blog posts like this, please!
- Did you know that Google provides [a free on-the-fly image 
re-sizer](https://carlo.zottmann.org/2013/04/14/google-image-resizer/)? 
I sure didn’t.

See you in a couple of weeks!

—eric