- From: Malvoz via GitHub <sysbot+gh@w3.org>
- Date: Wed, 28 Feb 2018 20:27:28 +0000
- To: public-css-archive@w3.org
Malvoz has just created a new issue for https://github.com/w3c/csswg-drafts:
== [css-mediaqueries] Proposal: "prefers-reduced-data" ==
Would CSSWG consider this proposal of detecting the [`Save-Data`](http://httpwg.org/http-extensions/client-hints.html#save-data) request header from the [Client Hint](https://github.com/httpwg/http-extensions#client-hints) HTTP extension?
### The `Save-Data` HTTP request header:
> ...a signal indicating explicit user opt-in into a reduced data usage mode on the client, and when communicated to origins allows them to deliver alternate content honoring such preference - e.g. smaller image and video resources, alternate markup...<br>
_[- http://httpwg.org/http-extensions/client-hints.html#save-data](http://httpwg.org/http-extensions/client-hints.html#save-data)_
<hr>
# Proposal
### The 'prefers-reduced-data' feature:
<table>
<tr>
<th>Name:</th>
<th>For:</th>
<th>Value:</th>
<th>Type:</th>
</tr>
<tr>
<td><code>prefers-reduced-data</code></td>
<td><code>@media</code></td>
<td><code>no-preference | reduce</code></td>
<td><code>discrete</code></td>
</tr>
</table>
### Example usage:
```
.image {
background-image: url("image/heavy.jpg");
}
@media (prefers-reduced-data: reduce) {
.image {
background-image: url("image/light.webp");
}
}
```
<hr>
Some relevant articles:
- [https://developers.google.com/web/updates/2016/02/save-data](https://developers.google.com/web/updates/2016/02/save-data)
- [https://www.ctrl.blog/entry/http-save-data](https://www.ctrl.blog/entry/http-save-data)
- [https://css-tricks.com/help-users-save-data/](https://css-tricks.com/help-users-save-data/)
Please view or discuss this issue at https://github.com/w3c/csswg-drafts/issues/2370 using your GitHub account
Received on Wednesday, 28 February 2018 20:27:32 UTC