Custom header via mailto link

Question

My goal is to have a link like

<a href="mailto:[email protected]?X-MyDetails=code924">Compose</a>

But as I can see the custom X-* headers are not respected by email agents - sent email does not contain X-MyDetails=code924 header.

I didn't find any confirmation that this is impossible in RFC but couldn't get it worked either.

Curd

Answer 1

I don't have any good news for you - it seems that even though the RFC supports having custom headers in mailto links, it's anybody's guess as to whether the email client will support it. In my testing I have found that Outlook does NOT support custom headers in mailtos, and Thunderbird DOES support them, so your mileage will vary significantly. From other searching on the internet, it seems that no other websites claiming to explain mailto links even mention this custom header ability, so I'd say that the general concensus is that mailtos with custom headers aren't supported.

Shrewmouse