mailto: provides a way of creating hyperlinks in websites that will tell your computer to open the default mail client and create a new email without the user having to copy and paste the email address. You can even pre-fill the message subject and content.
A simple mailto: hyperlink looks something like this:
<a href="mailto:example@email.com">Email me</a>You can read the full RFC documentation here: https://tools.ietf.org/html/rfc2368
Pretty useful. And it seems simple at first. But differing implementations across email clients can make it a deceptively difficult to create a mailto: link that works everywhere.
You might have a link opening fine in Mail on a Mac, only to realise that the links no longer work for Outlook on a PC. And then you turn to Stack Overflow where you decide you should probably be using semi-colons, not commas, but no one can really agree. Then you promptly just give up.
Even the Wikipedia page for mailto: gives instructions that won’t work by default on Outlook (which requires its users to actively turn on commas separation of email addresses).
Getting it right
Here is an example of a complex, robust, href link:
mailto:example@email.co…