Using "mailto" might be a bit of a no-no for some people, especially with all those spammers making millions from crawling the net for email addresses.
However, if you still want to use this feature, you may want to prefill some data in the email client. To do that, format your "href" with some optional arguments:
<a href="mailto:email@example.com?subject=title&body=something">Mail Me</a>
It would be a good idea to urlencode() the subject and body fields.
You can also prefill CC and BCC fields. See source for more information.
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