Up & Coming Extensions

Subscribe

Right Encoding

Adds the Character Encoding menu to the context menu

Rated 5 out of 5 stars (16)
4,365 users

Asterisk Click2Dial

This is an easy to use extention, select any number on a web page, right click to open the context menu which you can use to call this number.
Want it in your language, help us : https://translations.launchpad.net/click2dial-firefox-extension

Rated 5 out of 5 stars (5)
1,418 users

Super Date Format

Fully customize the date format of the Date/Received column.

Rated 4 out of 5 stars (9)
2,363 users

Google Calendar Tab

Adds the Google Calendar web interface as a new tab directly into Thunderbird. Creating and viewing events works just as it would in a browser like Firefox

Rated 4 out of 5 stars (76)
66,120 users

WordReference Translator

Open a tab with WordReference's translation for the selected word. Through a floating link, or by pressing "D" key.

Rated 3 out of 5 stars (30)
7,720 users

ThreadKey

Strike the 'T' key to sort messages by thread, strike the 'U' key to sort them unthreaded again, just like the 'G' key switches to Grouped By Sort view

Rated 4 out of 5 stars (23)
1,714 users

Get all mails

This extension provides a button for the mail toolbar to get mails for all accounts.

Rated 4 out of 5 stars (37)
9,791 users

Stylish-Custom

custom additions to Stylish extension.
brings back features from 0.5.9 and adds new features

I can't be bothered to change SC, so amo will allow it to be uploaded
http://choggi.org/misc/Stylish-Custom/

Rated 4 out of 5 stars (38)
2,681 users

Look Up in Dictionary

Looks up a selected word in OS X's Dictionary.app

Rated 5 out of 5 stars (40)
2,313 users

Reply Monitor

Keep track of your emails and replies (Lightning is required).
Note: the name of this add-on has been changed to Reply Monitor because the previous name is a registered trademark.

Rated 4 out of 5 stars (18)
1,439 users

Send Later

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

Rated 5 out of 5 stars (33)
52,384 users

QuickFolders (Tabbed Folders)

The "Swiss army knife" of folders. Turn your favorites into tabs - open folders and subfolders, move mails without scrolling around or searching. powerful + easy.

See new mail at a glance after automatic filtering - supports quickFilters addon!

Rated 5 out of 5 stars (109)
24,507 users

View Headers Toggle Button

This extension adds a toolbar button that allows the easy toggling of viewing all message headers.

Rated 3 out of 5 stars (30)
1,129 users

Play drums!

Just… play drums with your keyboard!

Rated 4 out of 5 stars (21)
1,050 users

Themes Menu

Adds Themes menu to the Tools and Titlebar menus. Includes toolbar icon.

Rated 4 out of 5 stars (13)
20,258 users

Lightning Featured

Organize your schedule and life's important events in a calendar that's fully integrated with your Thunderbird email. Manage multiple calendars, create your daily to do list, invite friends to events, and subscribe to public calendars.

Rated 3 out of 5 stars (1,830)
1,134,126 users

infoRSS

Displays RSS, Atom, Twitter, parsed HTML and NNTP feed in a scrolling area in the status bar. Compatible with podcasting RSS which can be downloaded directly. It's also a good Google email notifier.

Rated 4 out of 5 stars (92)
4,153 users

NestedQuote Remover

Remove nested quotes when replying to a...

Rated 3 out of 5 stars (16)
3,275 users

Dictionary Switcher for Thunderbird

Toggles spelling dictionaries automatically or manually and displays the currently selected one in the status bar.
Now merged with Dictionary Switcher v1.3 for Firefox/SeaMonkey

Rated 4 out of 5 stars (26)
10,869 users

Allow Empty Subject

Allows Thunderbird to send message without a subject.

Visit my Allow Empty Subject site for recent versions and news.

Rated 4 out of 5 stars (20)
1,071 users