Thunderbird reply template customization

This post contains some notes regarding the customization of the reply template in Thunderbird.

I adopted Thunderbird as my main email client some time ago, and since the progress in TB 3 I am very pleased with this piece of software. However, one of the features I wasn’t happy about is the Reply Template, the few lines that appear when you reply to a message.

Some time ago, I customized this using the hints given at – by creating a custom user.js file.

This was already some progress, but I wasn’t happy with the date formatting it produced, which looked like:

Mr X said the following on 8/9/10 9:28 PM:

I prefer explicit date/time formats such as 2010-09-08 21:28, so I searched for a way to configure this.

Looking through different epic bug entries such as Bug 107884 (Introduce editable templates for reply header strings) and Bug 218258 (Reply-to email lacks quoting of standard emailheaders), it becomes obvious that this is a underpowered feature, and possibilities of customization are limited. The only way to change this date format, is to indicate a different “locale” for the reply_header.

So I added a line
user_pref("mailnews.reply_header_locale", "en-US");
and started experimenting with different Locale strings, until I found one that produces the desired result:

// en-US -> 10/20/10 8:25 PM
// en-GB -> 20/10/2010 20:25
// en-CA -> 10-10-20 8:25 PM
// de-DE -> 20.10.10 20:25
// fr-ch -> 20.10.10 20:25
// hu-HU -> 2010.10.20. 20:25

In the end, through random trial&error testing, I found that the af-ZA string (which stands for Afrikaans – South Africa) produces the date formating I was looking for… so my user.js file now has this string:
user_pref("mailnews.reply_header_locale", "af-ZA");

Now my full custom code looks like this:

user_pref("mailnews.reply_header_type", 2);
user_pref("mailnews.reply_header_ondate", "------ original message ------\ndate: %s");
user_pref("mailnews.reply_header_separator", "\nfrom: ");
user_pref("mailnews.reply_header_authorwrote", "%s");
user_pref("mailnews.reply_header_colon", "\n");
user_pref("mailnews.reply_header_locale", "af-ZA");

Which produces the following end result:

------ original message ------
date: 2010-10-22 13:30
from: Name of sender

I still hope that the TB team will someday tackle this issue and offer more flexible customization options, but for now I am happy that I found this fix, which hopefully can be useful for others.