These are a ready make selection of some of the most popular buttons from the Custom Toolbar Button Maker

Thunderbird, Postbox

Reply to Sender Only

Reply only to the sender of the email

Reply only to the sender of the email.

Compatibility: Thunderbird, Postbox SeaMonkey

Rewrap

Rewrap

Rewraps the message text

Compatibility: Thunderbird, Postbox SeaMonkey

Send & Receive

Send and receive messages

Send all messages in the outbox and get all new messages.

Compatibility: Thunderbird, Postbox SeaMonkey

Skip Trash

Delete message with out sending it to the Trash

Delete a message with out sending it to the Trash. This will completely remove the message so that it can not be recovered.

Compatibility: Thunderbird, Postbox SeaMonkey

Toggle Read

Toggle Message Read Status

Toggle the Read status of the currently selected message.

Compatibility: Thunderbird, Postbox SeaMonkey

Toggle Starred

Toggle Starred Status

Toggle the starred status (look for the star next to the message).

Compatibility: Thunderbird, Postbox SeaMonkey

Toggle Tasks

Toggle the task bar

Toggle the task bar between visible and hidden.

Compatibility: Thunderbird, Postbox SeaMonkey