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

Thunderbird, Postbox

Go

Show the Go Menu

Show the Go Menu

Compatibility: Thunderbird, Postbox SeaMonkey

Ignored Threads

View Ignored Threads

View all the threads in the current folder that are set as ignored.

Compatibility: Thunderbird, Postbox SeaMonkey

Insert

Show Insert Menu

Show Insert Menu

Compatibility: Thunderbird, Postbox SeaMonkey

Message

Show the Message Menu

Show the Message Menu

Compatibility: Thunderbird, Postbox SeaMonkey

New Event

Add a new event to the calendar.

Add a new event into the calendar.

Compatibility: Thunderbird, Postbox SeaMonkey

New Task

Add a new task to the calendar.

Add a new task to the calendar.

Compatibility: Thunderbird, Postbox SeaMonkey

Open in Conversation

Open current message in Conversation

Open the current message in a conversation tab

Compatibility: Thunderbird, Postbox SeaMonkey

Options Menu

Show Options Menu

Show the options menu in the compose mail window.

Compatibility: Thunderbird, Postbox SeaMonkey

Paste As Quotation

Paste as a Quotation

Paste text so that it appears as a quoted message.

Compatibility: Thunderbird, Postbox SeaMonkey

Read

Read Message

Open the currently selected message in Thunderbird.

Compatibility: Thunderbird, Postbox SeaMonkey