Message Composition


To must occur only once

This add-on changes all but the first "to" to "cc" if there are multiple "to" when replying to an email.

Not yet rated
1 user
Added Oct. 15, 2020


Addons to edit and save eml file

Available on Github with MIT Licence :

Rated 1 out of 5 stars (1)
1 user
Added Oct. 14, 2020


Adds browser action icon to toolbar to open Telegram. See

Rated 5 out of 5 stars (1)
10 users
Added Oct. 5, 2020

Transfer Immunity

Transfer Immunity is a fast and secure add-on and SaaS service for sharing and transferring files. This high-fidelity, SaaS-based platform allows users to send large files to different destinations as attachments with emails.

Not yet rated
8 users
Added Sept. 16, 2020

Previous Colors

Quickly choose one of the previously selected colors for a message text

Rated 5 out of 5 stars (1)
210 users
Added Aug. 8, 2020


Quick & easy PGP encryption / decryption tool
* Save & use many public encryption keys to encrypt mail content
* Save & use many private decryption keys to decrypt mail content

Using openPGP.js

Open Source

Not yet rated
41 users
Added July 7, 2020


Insert signature helps you to insert usually used text by your customization.

Rated 4 out of 5 stars (6)
613 users
Added June 10, 2020

Expand mailing lists

Adds an 'expand lists' button to the compose window. It replaces all mailing lists with their contacts.

Rated 5 out of 5 stars (1)
81 users
Added March 28, 2020

FileLink for Plik

Upload large attachments to Plik and send the link by email

Not yet rated
482 users
Added March 20, 2020

Copy Address

Copy email address to clipboard.

Rated 4 out of 5 stars (4)
454 users
Added March 20, 2020

Limit non-BCC recipients

Check that number of non-BCC recipients does not exceed a parameter.

Rated 5 out of 5 stars (1)
83 users
Added Feb. 5, 2020

*cloud - FileLink for Nextcloud and ownCloud Featured

Upload large attachments to your Cloud and send the link by email

Rated 5 out of 5 stars (16)
7,892 users
Added Jan. 12, 2020

FileLink Provider for OwnCloud and NextCloud

Uploads your large attachments to your OwnCloud or NextCloud server and instead inserts a public link into your email.

Rated 4 out of 5 stars (9)
942 users
Added Dec. 27, 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 (5)
660 users
Added Oct. 8, 2019

changeQuote Requires Restart

It's an extension that changes the format of reply header.
You can choose between the standard Thunderbird reply header, a detailed reply header or a Customized reply header.
You can configure it in the Tools ->“Add-on Preferences -> changeQuote.

Rated 4 out of 5 stars (11)
761 users
Added Sept. 4, 2019

FileLink Provider for Box

Uploads your large attachments to your Box instead of sending them by email.

Rated 3 out of 5 stars (3)
11,186 users
Added May 21, 2019

Custom Sender Address and Reply Requires Restart

Select sender mail address based on the recipient and reply with the same address

Rated 5 out of 5 stars (2)
15 users
Added March 31, 2019

AutoCopy_rebirth Requires Restart

Lightweight add-on that automatically copies any highlighted text to clipboard.

Rated 5 out of 5 stars (4)
17 users
Added March 8, 2019

Use BCC Instead C Requires Restart

This addon prevents you accidentally sending an email to a large number of recipients without hiding their addresses from each other by using BCC. It is for TBv68.

Try my addon 'Limit non-BCC recipients'

Rated 4 out of 5 stars (4)
865 users
Added Feb. 19, 2019

TarotSignature Requires Restart

This version provides a custom button for the message composer.
You need to customize your toolbar of the message composer.
The signature is hard-coded into the source code.
The signature is NOT being inserted automatically on window-open.

Not yet rated
0 users
Added Feb. 13, 2019