Making it easier to reply to email digests

Mailing lists are still a common way of communicating in teams. If the volume is high, a convenient option is to receive a digest that delivers several sent messages in a single email.

• Problem: Replying to one of the messages in a digest is difficult.
  • You need to copy the subject and the text you want to reply to.
  • Your answer will not appear correctly threaded in the mailing list archives, because threading relies on the correct message ID being provided via the In-Reply-To header.
• Non-solution – don’t use digests: To avoid digests, you could automatically file messages from a mailing list to a common folder (by filtering who sends them). Alas, many mobile devices do not support that kind of filtering and make it difficult to access folders other than the inbox.
• Solution: one mailto link embedded next to each message in the digest.
  • Clicking that link opens a new message in your email client, with Subject, To, and In-Reply-To already filled in.
  • Supporting In-Reply-To: Most email clients don’t support the In-Reply-To header in mailto links, they simply ignore it [if you are aware of any that do support it, let me know]. The work-around is to additionally put the ID of the message one replies to in the body of the message. Then you can manually add an In-Reply-To header and fill in the correct value.

With that solution, one answers to a message in the digest by first copying the content one wants to quote (putting all of that content into the link would create space problems) and then clicking on the mailto link.

Demo of a a message plus a mailto link (clicking on the link should open a new message in your default email client):

    From: John Doe <joe@example.com>
    Date: May 17, 2011 4:20:08 GMT+02:00
    Subject: I have a question [Reply]

    Why is there something and not nothing?

Related reading:

1. RFC 2368 - The mailto URL scheme
2. Generate emails with mailto URLs and Python [includes a quick intro to the syntax of mailto links]
3. Enabling In-Reply-To headers in Mozilla apps: How to Add an Arbitrary Custom Header to Email in Mozilla Thunderbird, Mozilla SeaMonkey or Netscape