Extensions by Weekly Downloads


ImportExportTools Requires Restart

Adds some tools to import and export folders and messages

Rated 4 out of 5 stars (175)
14,511 weekly downloads

Lightning Requires Restart

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 (1,847)
12,194 weekly downloads

Provider for Google Calendar Requires Restart

Allows bidirectional access to Google Calendar

Rated 4 out of 5 stars (966)
7,765 weekly downloads

Auto Resize Image Requires Restart

Resizer for inline and attachment images (JPEG, PNG, BMP and GIF image formats).
All platforms are supported (Windows, Linux and Macintosh).

Rated 4 out of 5 stars (30)
6,797 weekly downloads

FlashGot Mass Downloader Requires Restart

Download all the links, movies and audio clips of a page at the maximum speed with a single click, using the most popular, lightweight and reliable external download managers.

Rated 5 out of 5 stars (827)
6,595 weekly downloads

Enigmail Requires Restart Featured

OpenPGP message encryption and authentication for Thunderbird and SeaMonkey.

Rated 4 out of 5 stars (201)
5,827 weekly downloads

SQLite Manager Requires Restart

Manage any SQLite database on your computer.

Rated 4 out of 5 stars (289)
3,746 weekly downloads

gContactSync Requires Restart

Synchronizes contacts & groups between Thunderbird or SeaMonkey and Google Contacts. Imports Facebook friends, contacts you follow on Twitter, and more.

Rated 4 out of 5 stars (232)
3,090 weekly downloads

Manually sort folders Requires Restart

This extension allows you to manually sort (order) your folders in the folder pane of Thunderbird or automatically sort them, but in a better way. This extension also allows you to re-order accounts in the folder pane.

Rated 4 out of 5 stars (174)
3,024 weekly downloads

CardBook Requires Restart Featured

A new Thunderbird address book based on the CardDAV and vCard standards.

Twitter: @CardBookAddon
Forum: https://cardbook.6660.eu/

Rated 4 out of 5 stars (154)
3,023 weekly downloads

Mail Merge Requires Restart Featured

Mass Mail and Personal Mail

Rated 5 out of 5 stars (154)
2,420 weekly downloads

Send Later Requires Restart

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

Rated 5 out of 5 stars (112)
2,117 weekly downloads

Password Exporter

This add-on allows you to export your saved passwords and disabled login hosts using XML or CSV files that can be imported later.

Note: This add-on won't work in Firefox 57. It may eventually if the APIs to access passwords are implemented.

Rated 4 out of 5 stars (531)
2,094 weekly downloads

LookOut (fix version) Requires Restart

LookOut is a plugin which allows Thunderbird to interface with Microsoft's mail tools by decoding metadata and attachments encapsulated/embedded in a TNEF encoded attachment (aka winmail.dat).
Support: Thunderbird and SeaMonkey

Rated 4 out of 5 stars (21)
1,757 weekly downloads

ExQuilla for Microsoft Exchange Requires Restart

Thunderbird email accounts connecting to Microsoft Exchange Web Services.

Rated 3 out of 5 stars (102)
1,638 weekly downloads

Element Hiding Helper for Adblock Plus

Fight the text ads! Element Hiding Helper is a companion extension for Adblock Plus meant to make creating element hiding rules easier.

Rated 5 out of 5 stars (467)
1,606 weekly downloads

QuickNote Requires Restart

A simple note-taking extension.

Rated 5 out of 5 stars (200)
1,541 weekly downloads

Image Zoom Requires Restart

Adds zoom and rotation functionality for images...

Rated 4 out of 5 stars (353)
1,416 weekly downloads

MinimizeToTray revived Requires Restart

Minimizes windows into the system tray.

Rated 4 out of 5 stars (360)
1,368 weekly downloads

Theme Font & Size Changer for ThunderBird

Theme Font & Size Changer lets you change the global font size and font family used for the user interface in Firefox. Design your browser with your favorite font.

Rated 4 out of 5 stars (42)
1,342 weekly downloads