The new Opera 10.0 includes a new feature that allows users to click on mailto: links and have them open in web mail providers, such as Gmail, Yahoo! Mail, and Windows Live Hotmail. This is particularly useful for individuals that primarily use web mail instead of a standalone e-mail client.
In a clean install, clicking a mailto: link will trigger the e-mail client selection dialog, which allows users to choose between using Opera Mail, the system default mailer, and a couple of random web mail providers. Users can change their settings in Preferences > Advanced > Programs by editing the “mailto” handler.
This feature works via a list of web mail providers in the webmailproviders.ini file in the “defaults” sub-directory of the Opera program directory. On Windows, for instance, the file will be in “C:\Program Files\Opera\defaults\”. On OS X, the file is in the Opera.app package in the “Contents/Resources/defaults/” directory. Opera will need to be restarted to pick up new/changed entries in the file.
For whatever reason, they don’t include GMail by default, if you would like to use it add the following code to the bottom of the webmailproviders.ini
[Gmail]
ID=1
URL=https://mail.google.com/mail/?view=cm&fs=1&to=%t&su=%j&body=%m&cc=%k&bcc=%l
ICON=http://mail.google.com/favicon.ico
