[necolas]

Unfortunately, at the time when Ian didn't seem to care about the issue of responsive images, I asked him about the possibility of using the existing `<img>` element and he said it was pointless to try and modify existing image parsing. Forget it.

Now, he decides that actually this is the way to go. Frustrating.

For reference, in the email linked above, Ian Hickson said:

> So why not just give the UA the characteristics and a template to use to build the file names itself? That way we still give the UA all the same information, but it is much less verbose and still solves all the same use cases. Thus:

   <img src="[e-mail]" alt=""
        src-template="face-%w-%h@%r.jpeg"
        src-versions="600x200x1 600x200x2 200x200x1"></code>

[hoppipolla]

This doesn't modify parsing. Modifying parsing would be something like allowing <img> to have child elements. Adding extra attributes to an element requires no changes to the parser.