[html5] Detect support for tel: uri scheme or better markup for phone numbers

[Ian Hickson]

On Thu, 10 Jan 2013, Markus Ernst wrote:
> 
> Is there a recommended and reliable way to detect whether tel: links are 
> supported?

Not currently.

In theory, any Web page can register as a handler for tel:. One could 
imagine e.g. Google Voice handling that protocol on a desktop browser.

We could provide an API that exposes which schemes are available, but 
really a better solution would probably be for browsers to detect that the 
link doesn't do anything (because they and their OS don't support the 
scheme) and then not making :link/:visited match it.


> Personnally I think that tel: and mailto: uri schemes are actually not a 
> satisfying way to mark up phone numbers resp. e-mail addresses. 
> Something like <span role="phonenumber" target="+0123456789"> would be 
> better, as UAs were free to apply all kind of functionalities they are 
> configured to, and non-supporting browsers would just ignore them 
> instead of displaying ugly error messages.

(or doing nothing)

Yeah, it is kind of weird how non-fetchable-resources are marked up in 
this way. Not sure what to do instead though. There's a lot of momentum 
behind the current mechanism.

-- 
Ian Hickson               U+1047E                )\._.,--....,'``.    fL
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Things that are impossible just take longer.   `._.-(,_..'--(,_..'`-.;.'