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

Thunderbird, Postbox

New Task

Add a new task to the calendar.

Install New Task

Download New Task

Compatibility: Thunderbird, Postbox SeaMonkey

Next Message

Get the next message. Unlink the default Thunderbird buttons this just go to the next in the list, or if shift is pressed, the next unread.

Install Next Message

Download Next Message

Compatibility: Thunderbird, Postbox SeaMonkey

Plain Text Paste

Paste text into Thunderbird without any formatting.

Install Plain Text Paste

Download Plain Text Paste

Compatibility: Thunderbird, Postbox SeaMonkey

Previous Message

Get the previous message. Unlink the default Thunderbird buttons this just go to the previous in the list, or if shift is pressed, the previous unread.

Install Previous Message

Download Previous Message

Compatibility: Thunderbird, Postbox SeaMonkey

Read

Open the currently selected message in Thunderbird.

Install Read

Download Read

Compatibility: Thunderbird, Postbox SeaMonkey

Tasks In View

Toggle the Task in View panel in Sunbird.

Install Tasks In View

Download Tasks In View

Compatibility: Thunderbird, Postbox SeaMonkey

Toggle Read

Toggle the Read status of the currently selected message.

Install Toggle Read

Download Toggle Read

Compatibility: Thunderbird, Postbox SeaMonkey