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

Thunderbird, Postbox

Edit Draft

Edit Saved Draft or Message

Edit a message that you have saved as a draft.

Compatibility: Thunderbird, Postbox SeaMonkey

Format

Show the Format Menu

Show the Format Menu

Compatibility: Thunderbird, Postbox SeaMonkey

Forward Inline

Forward message as part of the email

Forward the current message as part of the email.

Compatibility: Thunderbird, Postbox SeaMonkey

Get Inbox

Change Focused Folder to the Inbox

Change the currently selected folder to your Inbox.

Compatibility: Thunderbird, Postbox SeaMonkey

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

Open in Conversation

Open current message in Conversation

Open the current message in a conversation tab

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