From MozillaZine Knowledge Base

This article was written for Thunderbird but also applies to Mozilla Suite / SeaMonkey (though some menu sequences may differ).

When replying to messages, you may want your reply text to appear above (also known as top posting) or below the quoted text by default. This can be set differently for each account. Go to "Tools -> Account Settings", and then for the account you want to change select "Composition & Addressing". Using the drop-down list on the right, choose the reply position you want to use and click "OK". There is also an option to choose whether signature blocks should go at the very bottom of the message (the default), or directly beneath a top-posted response (above the quoted material). Note that if the signature is placed above a quoted message, the separator line ("-- ") is not used, as this would cause some mail clients to strip off everything below it upon replying.

The mail.identity.default.reply_on_top preference sets the default value for the reply text position for each account/identity. It defaults to 0, to have the reply at the bottom. You can use the Config Editor at Tools -> Options -> General to set it to 1 to have the reply on top.

Traditional netiquette (especially on Usenet and mailing lists) is to reply contextually beneath quoted material, trimming down the quotes to the minimum needed to establish context. Also known as inline, interspersed and interleaved posting, this does not always put your entire reply beneath all of the quoted material, because if you are replying to multiple paragraphs, each section of the reply would be beneath the quote of the paragraph to which it is responding. Some people prefer to start their cursor at the top of the message in order to facilitate moving down through the message and trimming the quotes before typing replies contextually. In this case, they would place the signature block at the very bottom of the message.

Changes with Thunderbird 24.0

Following frequent requests in forums and the choice of default in other mail clients, Thunderbird (but not SeaMonkey) will change the default behavior for new mail accounts to balance the different interests with its 24.0 release:

• when setting up the first mail account, it will default to "reply above the quote" with the signature-placement default remaining at "below the quote"
• when setting up additional mail accounts, reply and signature-positioning preferences will be selected according to your default account (usually the first mail account you've set up, unless you've explicitly changed it later)
• any existing accounts you had before the 24.0 will not change either setting
• for news accounts, the default remains to reply below the quote unless you've modified mail.identity.default.reply_on_top

See also

• Modify Thunderbird settings
• Quote bars
• Quote only selected text when replying
• Reply above quoted message

External links

• Change quote and reply format extension
• Dan's Mail Format Site: information on mail reply and quoting format
• QuoteAndComposeManager extension provides several options for the quoting format and the headers layout when replying or forwarding messages. It used to be called the RealBorders extension.
• Wikipedia: Posting styles