Send Later Requires Restart
True "Send Later" functionality to schedule the time for sending an email.
Mail Merge Requires Restart Featured
Mass Mail and Personal Mail
Stationery Requires Restart
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!
Clippings Requires Restart
Save frequently-entered text for pasting later.
Check and Send Requires Restart
Check the message contents and addresses before you send the message...
SmartTemplate4 Requires Restart
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.
Flex Confirm Mail Requires Restart
Confirm mail address and attachments based on flexible rules.
ThunderPEC Requires Restart
ThunderPEC semplifica la gestione della Posta Elettronica Certificata (PEC) e delle comunicazioni PCT e FatturaPA in Thunderbird.
Highlighter Requires Restart
Quickly highlight some text in Thunderbird message composing windows.
Markdown Here Requires Restart
Write your email in Markdown, then make it pretty.
Toggle Word Wrap Requires Restart
Toggle word wrapping and PRE element wrapping in the message composition and HTML display windows, respectively.
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.
Extra Format Buttons Requires Restart
Adds a font size (in pixels), strikethough, subscript and superscript buttons to Thunderbird's Compose Window.
BorderColors GT Requires Restart
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.
Email signature for Thunderbird - WiseStamp Requires Restart
Switch Thunderbird email signatures. Supports Gmail, Yahoo, AOL & Outlook webmails. Youtube, Facebook, Twitter icons & more
Emoji Menu Requires Restart
Adds the ability to easily insert emojis into your composed messages in Thunderbird.
SmilieInserter Plus Requires Restart
Insert smilies in messages.
AVIM Requires Restart
Vietnamese-language input method editor (IME). Type diacritics directly into any Web page, Web app, or dialog box. Convenient, comprehensive, secure.
Bộ gõ tiếng Việt cho phép đặt dấu trực tiếp vào bất kỳ trang Web, ứng dụng Web, hộp thoại.
Remembers the language you use with a person or group of people, and switches the spellchecker language automatically for you next time. You do not have to do it manually any more. It remembers and switches it for you.