For those interested the API it's using is navigator.registerProtocolHandler.<p><a href="http://www.w3.org/TR/html5/timers.html#custom-handlers" rel="nofollow">http://www.w3.org/TR/html5/timers.html#custom-handlers</a><p><a href="http://updates.html5rocks.com/2011/06/Registering-a-custom-protocol-handler" rel="nofollow">http://updates.html5rocks.com/2011/06/Registering-a-custom-p...</a>
This is an odd wording: "Allow ... [No] [Use Gmail]". This may confuse people who will think that in order to use Gmail, you have to click this button.<p>Oh, I should submit a bug report instead of posting here.
And if you want to open mailto links in Gmail with Firefox (and Opera I guess): <a href="http://updates.html5rocks.com/2012/02/Getting-Gmail-to-handle-all-mailto-links-with-registerProtocolHandler" rel="nofollow">http://updates.html5rocks.com/2012/02/Getting-Gmail-to-handl...</a>
On the front page of my website where I display a mailto link, I also have GMail and Yahoo specific compose links:<p>"Email: mymailtolink (Compose with GMail/Yahoo)"<p><a href="https://grepular.com/" rel="nofollow">https://grepular.com/</a><p>I wrote some JavaScript code a while back which would automatically detect if a visitor was logged in to GMail, and would replace all mailto links on my page with GMail compose links instead. I never put it live on my site though as the process of detecting if a user is logged in to gmail is pretty dodgy. In case you're interested in the code, or the detection process:<p><a href="https://grepular.com/Abusing_HTTP_Status_Codes_to_Expose_Private_Information" rel="nofollow">https://grepular.com/Abusing_HTTP_Status_Codes_to_Expose_Pri...</a>
Edit:
Mea Culpa.
I see this is for desktop links.<p>I clicked the help last night when this popped up and must have read it incorrectly.<p>However, this can still cause problems if you have 2 email clients, say Outlook for my corporate mail and gmail for my personal mail.<p>IT departments are going to love this.
A complete aside, but the pushState/client side rendering implementation on the blog surprised and confused me massively. It seems like the wrong tool for a blog.
It took them a while to build that in. So secure and fast, but something as basic as this (which the competition got since day one) has no priority apparently.