Message Composition

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Send Later

True "Send Later" functionality to schedule the time for sending an email.

Rated 5 out of 5 stars (33)
56,849 users

Mail Merge Featured

Mass Mail and Personal Mail

Rated 5 out of 5 stars (133)
51,033 users

Stationery

Extension to mimic Outlook Express Stationery.
Allow you to use HTML files as templates for mail. Also allow custom template in replies or forwarded mail!

Rated 4 out of 5 stars (81)
43,229 users

Clippings

Save frequently-entered text for pasting later.

Rated 4 out of 5 stars (159)
36,571 users

Check and Send

Check the message contents and addresses before you send the message...

Rated 4 out of 5 stars (24)
25,652 users

SmartTemplate4

SmartTemplate4 offers an easy way to automatically create customized replies by auto-inserting various mail headers. Templates can be created for every account as well as for the default (all email accounts). Also supports the Stationery Add-on.

Rated 5 out of 5 stars (48)
19,133 users

ThunderPEC

ThunderPEC semplifica la gestione della Posta Elettronica Certificata (PEC) in Thunderbird.

Rated 4 out of 5 stars (6)
12,791 users

Transliterator No Restart

As-you-type phonetic conversion of text from one alphabet to another, as well as transliteration/detransliteration of selected text anywhere within documents. Supports multiple languages and custom transliteration schemes.

Rated 5 out of 5 stars (75)
8,011 users

Markdown Here

Write your email in Markdown, then make it pretty.

Rated 5 out of 5 stars (14)
6,488 users

Flex Confirm Mail

Confirm mail address and attachments based on flexible rules.

Rated 1 out of 5 stars (1)
5,327 users

BorderColors GT

How many time you sent an email from your wrong email address?
This add-ons allows you assign a different color to the compose window border for each of your email addresses. So you can immediately view from what account are you writing.

Rated 4 out of 5 stars (7)
3,945 users

SmilieInserter Plus

Insert smilies in messages.

Rated 5 out of 5 stars (17)
3,654 users

AVIM

An input method editor (IME) for Vietnamese. Type Vietnamese diacritics directly into any Web page, Web app, or dialog box.
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Bộ gõ tiếng Việt cho phép đặt dấu trực tiếp vào bất kỳ trang Web, ứng dụng Web, và hộp thoại.

Rated 5 out of 5 stars (30)
3,141 users

Email signature for Thunderbird - WiseStamp

Switch Thunderbird email signatures. Supports Gmail, Yahoo, AOL & Outlook webmails. Youtube, Facebook, Twitter icons & more

Not yet rated
2,899 users

Automatic Dictionary No Restart

Extension that remembers the language of the spellchecker used when composing and switches to it every time you write to that person.

Rated 5 out of 5 stars (17)
2,756 users

EnForward

Save your email into Evernote by forwarding it to Evernote email address.
Before you use it, you need to specify your Evernote email address (see the screenshot).

This function can be invoked by "Forward to Evernote" in the context menu.

Rated 5 out of 5 stars (4)
2,210 users

Flexible Identity

Selects an identity based on the recipients list when sending an email

Rated 4 out of 5 stars (19)
1,740 users

Color Text Compose Buttons

Adds Text Color Buttons in Compose Toolbar and More: Pixel FontSize, Strikethough, Sub & Superscript, Lower & UpperCase. Also provide Tools: Insert iframe, Launch MathType, Maths & Greek Symbols, Load Template Variables and Duplicate Compose Window.

Rated 5 out of 5 stars (14)
1,616 users

Get before Send

Get messages for the account which is bound to the identity then send the message when you click the toolbar button or the menu item. If your SMTP sever authenticates using POP(IMAP) before SMTP, the extension is useful.

Rated 5 out of 5 stars (2)
1,522 users

DL for Thunderbird

Allows to convert large attachments to links automatically without 3rd party providers.

Rated 5 out of 5 stars (2)
1,442 users