a glob of nerdishness

As reported by Gus Mueller, remembered by Fraser Speirs and reverse engineered by dragging messages from Mail.app into a rich TextEdit document: Mail.app now supports permalink URLs to messages.

The URLs are just “message:” followed by the Message-Id, which should be URL encoded. So if your Message-Id is “<abc%20071105@sender.org>” — the angle brackets are considered part of the Message-Id — the URL becomes “message:%3Cabc%2520071105@sender.org%3E”, although “message:<abc%2520071105@sender.org>” will also work from Safari’s address bar.

This is basically just the mid: URL scheme with a different scheme name. Why they used “message” instead of “mid” is strange, especially since on the Flying Meat forum there’s a discussion of links provided by an add-on called MailTags that use a similar URL scheme. These have an extra “//” before the Message-Id, and make Mail grumble that “No associated application could be found”. Update: On second try the extra “//”s seem to work as well, so the real question is why MailTags, not Apple, didn’t use the “mid:” form.

To get the Message-Id, select “Long headers” or “Raw Source” in Mail’s “View > Message” menu. You can also drag a message from Mail into a rich text field to get the hyperlink. Enjoy!

Update: John Gruber has put together a more definitive article on this topic, though he doesn’t make mention of the (seemingly historical) “mid:” URL scheme.