If you use Gmail you may become frustrated when you click a mailto: link by accident and now your desktop client of Outlook or Mail starts up.
Thanks to navigator.registerProtocolHandler() you can wire up Gmail as your default mail client for all mailto: links in Chrome and Firefox.
Here's how:
First, open up a Gmail tab. You must do this from the Gmail tab.
Open your javascript console (cmd-opt-j on Mac, ctrl-shift-j on Windows) and enter:
and enter:
navigator.registerProtocolHandler("mailto", "https://mail.google.com/mail/?extsrc=mailto&url=%s", "Gmail");
Accept the confirmation from the browser.
This is how you can cross check in the settings.
Click this mailto: link to test out your new Gmail mailto hookup!