Mozilla Mailnews FAQ

How do I customize the "Author wrote" reply intro line?

The standard reply header "[author] wrote:" can be changed to virtually anything, to make your e-mails more personalized. Add and modify the following code to your user.js file, instructions are in the comments:

// Change the reply header
// 0 - No Reply-Text
// 1 - "[Author] wrote:"
// 2 - "On [date] [author] wrote:"
// 3 - User-defined reply header. Use the prefs below in conjuction with this:
user_pref("mailnews.reply_header_type", 3);

// If you set 3 for the pref above then you may set the following prefs.
user_pref("mailnews.reply_header_authorwrote", "%s said the following");
user_pref("mailnews.reply_header_ondate", "on %s");
user_pref("mailnews.reply_header_separator", " ");
user_pref("mailnews.reply_header_colon", ":");
// The end result will be [authorwrote][separator][ondate][colon]

Changing the date display format:
user_pref("mailnews.reply_header_locale", "de-DE");
(de-DE is the German format: 25.05.02. You can use any format you like, for example en-GB for British format, or DK for Danish. Check out Edit -> Preferences -> Navigator -> Languages for exmaples)

If you have put "<br>" in your reply intro, and find it not to work, try "\n".