[whatwg] The sizes="" attribute for rel=icon

[Kornel Lesinski]

On Wed, 28 May 2008 13:07:50 +0100, Ian Hickson <ian at hixie.ch> wrote:

>> I'm afraid that this could cause trouble (every visitor downloading icon
>> that's 20–300 times larger than typical favicon). Why not use
>> rel=application-icon or rel=appicon?
>
> I don't understand the question.

<link rel=icon> is currently used for favicons. Favicons are expected to  
be small (in byte size). Current browsers always download favicons on  
every website.

If page author adds high-quality image using rel=icon (like Vista's 100KB  
icon or Leopard's 300KB monstrosity), it may significantly increase site's  
traffic (these icons will be downloaded by every visitor rather than only  
those who create a shortcut).

e.g.:
<link rel=icon sizes=16x16 href=tinyicon.png>
<link rel=icon sizes=256x256 href=hugeicon.ico>

In current browsers this will not work as expected - browsers will  
download the big application icon, which is going to be order of magnitude  
larger (in byte size) than a favicon.

Using rel=application-icon instead of rel=icon would avoid this problem.  
Another solution would be to suggest that authors specify favicon as last  
in the tree order (example it the spec lists favicon first).

-- 
regards, Kornel Lesiński