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Test Pilot for Thunderbird

Add-on has now been discontinued, see below.

Rated 1 out of 5 stars (15)
25,920 users

ThunderPEC Requires Restart

ThunderPEC semplifica la gestione della Posta Elettronica Certificata (PEC) e delle comunicazioni PCT e FatturaPA in Thunderbird.

Rated 5 out of 5 stars (12)
25,476 users

DOM Inspector Requires Restart

DOM Inspector is a tool that can be used to inspect and edit the live DOM of any web document or XUL application. The DOM can be navigated using a two-paned window displaying a variety of different views on the document and all nodes within.

Rated 5 out of 5 stars (77)
25,263 users

Thunderbird Conversations

This addon provides a conversation view for Thunderbird, grouping messages together and allowing you to reply "inline" thus providing a more efficient workflow.

Rated 4 out of 5 stars (441)
24,704 users

Lightning Calendar Tabs Requires Restart

Displays tabs which allows quick navigation between time periods in Lightning calendar. All views of calendar are supported. Color of tab texts can be adjusted.

Rated 4 out of 5 stars (13)
24,203 users

Display Mail User Agent Requires Restart

Displays icon for user agent of received mails.

Rated 4 out of 5 stars (111)
23,900 users

ExQuilla for Exchange Requires Restart

Thunderbird email accounts connecting to Microsoft Exchange Web Services.

Rated 3 out of 5 stars (115)
23,728 users

Confirm-Address Requires Restart

Confirm E-mail address before sending mail

Rated 4 out of 5 stars (53)
23,250 users

QuickFolders (Tabbed Folders) Requires Restart

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 (128)
21,775 users

XNote++ Requires Restart

Persistent sticky notes for Thunderbird associated to mails.
This is a port to Thunderbird >= 3 based on XNote 2.1.0 ( https://addons.mozilla.org/en-US/thunderbird/addon/3093 ) with bugfixes and additional features.

Rated 5 out of 5 stars (75)
21,238 users

TbSync

TbSync is a central user interface to manage cloud accounts and synchronize their contact, task and calendar information with Thunderbird.

Rated 5 out of 5 stars (55)
19,737 users

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.

Rated 5 out of 5 stars (54)
18,173 users

Theme Font & Size Changer (fixed)

Fixed version (no 90 day timer till silent failure) of the popular "Theme Font & Size Changer for Thunderbird" addon

Rated 4 out of 5 stars (33)
17,997 users

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 (33)
16,805 users

Check and Send Requires Restart

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

Rated 4 out of 5 stars (31)
16,803 users

LightningButton Requires Restart

Toolbar-Buttons for Lightning; advances the feature to get rid of the tabbar.

Rated 4 out of 5 stars (16)
16,661 users

StartupMaster

Asks for the master password at startup (fixes multiple password prompt)

Rated 4 out of 5 stars (279)
16,195 users

Flex Confirm Mail Requires Restart

Confirm mail address and attachments based on flexible rules.

Rated 3 out of 5 stars (5)
15,940 users

Calendar Tweaks Requires Restart

Allows several tweaks to the Thunderbird/Lightning calendar user interface including new selection styles and repeating event icons. Mimics the colors and styles found in MS Outlook.

Rated 4 out of 5 stars (58)
14,979 users

Contact Tabs Requires Restart

Contact Tabs enhances Thunderbird to give you quick access to all your contacts directly from Thunderbird's main window: Use the powerful search field to find your contacts and open them in a new tab for viewing and editing.

Rated 4 out of 5 stars (54)
14,594 users