This add-on changes all but the first "to" to "cc" if there are multiple "to" when replying to an email.
Addons to edit and save eml file
Available on Github with MIT Licence :
Adds browser action icon to toolbar to open Telegram. See https://thunderbird-essentials.thomas-bandl.de/wordpress/2020/10/04/telegram-button/
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.
Quickly choose one of the previously selected colors for a message text
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
Insert signature helps you to insert usually used text by your customization.
Adds an 'expand lists' button to the compose window. It replaces all mailing lists with their contacts.
Upload large attachments to Plik and send the link by email
Copy email address to clipboard.
Check that number of non-BCC recipients does not exceed a parameter.
Upload large attachments to your Cloud and send the link by email
Uploads your large attachments to your OwnCloud or NextCloud server and instead inserts a public link into your email.
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.
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.
Uploads your large attachments to your Box instead of sending them by email.
Custom Sender Address and Reply Requires Restart
Select sender mail address based on the recipient and reply with the same address
AutoCopy_rebirth Requires Restart
Lightweight add-on that automatically copies any highlighted text to clipboard.
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.
IT WILL NOT BE UPDATED FOR TBv78.
Try my addon 'Limit non-BCC recipients'
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.