Newest Extensions


ShowFolderSize-T Requires Restart

Shows folders size on disk.

This add-on is a fork of ShowFolderSIze.

Not yet rated
53 users
Added Nov. 13, 2019

Display Mail User Agent T Requires Restart

Displays the mail program with which the selected mail was written

*This addon is compatible with Thunderbird after Web Extesnsions support. Since development and operation check are done on Daily, it may not work on normal Thunderbird.

Rated 5 out of 5 stars (2)
534 users
Added Nov. 2, 2019

Minimize on Close Requires Restart

Causes Thunderbird's main window to minimize instead of closing. You can still close Thunderbird through the menu.

Rated 4 out of 5 stars (12)
1,336 users
Added Oct. 27, 2019

Open In Conversation Requires Restart

Make the default message list action be "Open Message in Conversation" when double-clicking or using the "Enter" key to open an email from the message list.

Rated 5 out of 5 stars (1)
30 users
Added Oct. 21, 2019

Auto Address Cleaner T Requires Restart

Remove comment, display name from addresses before sending mail.

This add-on is a fork of Auto Address Cleaner.

Rated 5 out of 5 stars (1)
233 users
Added Oct. 16, 2019

G Suite in tab Requires Restart

Abrir URL de G Suite en pestañas (por el momento solo están los botones de Calendar y Keep)

Not yet rated
41 users
Added Oct. 13, 2019

Open Tab Requires Restart

Link open in new tab.

Not yet rated
42 users
Added Oct. 11, 2019

Toggle Word Wrap Requires Restart

Toggle word wrapping and <PRE> element wrapping in the message composition and HTML display windows, respectively. Based on original version by Kaspar Brand.

Rated 5 out of 5 stars (2)
190 users
Added Oct. 8, 2019

M-Hub Lite

Add Microsoft Office 365 Tabs to Thunderbird! Services supported by M-Hub Lite: Calendar, People, OneDrive, Word, Excel, PowerPoint, & Bing. Need business or enterprise support? Get M-Hub Pro:

Not yet rated
68 users
Added Oct. 3, 2019

TabAddressbook Requires Restart

Creates a tab for the addressbook.

Rated 4 out of 5 stars (2)
177 users
Added Sept. 9, 2019

changeQuote Requires Restart

It's an extension that changes the format of reply mails.

Rated 5 out of 5 stars (1)
66 users
Added Sept. 4, 2019

Custom sync interval for Lightning Calendar Requires Restart

Allows custom synchronization intervals for remote calendars imported by Lightning Calendar (no fiddling in about:config necessary)

Not yet rated
83 users
Added Aug. 21, 2019

Remove Duplicates Requires Restart

Removes duplicate messages

Rated 4 out of 5 stars (5)
380 users
Added Aug. 19, 2019

OppositeTodaySubpane Requires Restart

Today subpane is a emblem of Thunderbird.
When today pane is hidden for a wide view,
someone feels sorry not to have this today subpane on screen.
It is to remain today subpane on folder and subscription pane.
send a gift to a friend Eunjo.

Not yet rated
18 users
Added Aug. 17, 2019

Copy Patch Requires Restart

Copy email content to clipboard for application as patch.

Applies some filters, e.g. Outlook Safe Link unmangling, to ensure patch cleanness.

Not yet rated
7 users
Added Aug. 16, 2019

Autocrypt Requires Restart

E-Mail encryption that gets out of your way. Compatible with Autocrypt and OpenPGP.


Caution: This extension can not be used together with Enigmail. Please remove Enigmail before installing.

Rated 4 out of 5 stars (7)
116 users
Added Aug. 13, 2019


Put task view up to read document of long sentences.
Put task view neutrally to read tree lists.
Put task view vertically to read document in which records are many.
praise Cardinal Soo-Hwan, Kim.

Rated 1 out of 5 stars (2)
29 users
Added Aug. 9, 2019

Night and Day Dynamic

A theme that switches between sun and moon based on time of day.

This is the canonical example dynamic theme published by Mozilla:

Rated 4 out of 5 stars (1)
641 users
Added July 27, 2019

Profile Switcher Requires Restart

Adds options to launch other profiles.

Rated 5 out of 5 stars (2)
472 users
Added July 24, 2019

ImportExportTools NG Requires Restart Featured

Adds tools to import/export messages and folders (NextGen)

Rated 4 out of 5 stars (24)
38,588 users
Added July 15, 2019