Recently Updated Extensions
quickFilters Requires Restart
Quickly generate mail filters on the fly, by dragging and dropping mails and analyzing their attributes. Create a filter in less than 10 seconds, it's as easy as: drag, click, click.
By popular demand, supports SORTING filters alphabetically.
PlayFlash 64bit Requires Restart
Flash player plugin - unofficial xpi repack for 64bit browsers. Use when official plugin installer is not suitable. All binary files are copyrighted by their authors and distributed for free.
PlayFlash 32bit Requires Restart
Flash player plugin - unofficial xpi repack for 32bit browsers.
Use when official plugin installer is not suitable.
All binary files are copyrighted by their authors and distributed for free.
OpenPGP message encryption and authentication for Thunderbird and SeaMonkey.
Mail Merge Requires Restart
Mass Mail and Personal Mail
CardDAV Browser Requires Restart
A utility to browse vCards stored on a CardDAV server.
QuoteCollapse Requires Restart
Collapse and expand quotes. Please see the extension homepage for further information.
Note that MozDev has shut down long ago (mailing list etc). Add-On homepage, source code and issue tracker are on GitHub, as linked on this page.
Auto delete cookies, localStorage and IndexedDB objects as soon as they become unused
Webmaster SAPE Requires Restart
Toolbar contains a set of functions, which expands the abilities of webmasters and optimizers, when working in the interface of SAPE exchange.
Strike the 'T' key to sort messages by thread, strike the 'U' key to sort them unthreaded again, just like the 'G' key switches to Grouped By Sort view
ReminderFox Requires Restart Featured
ReminderFox displays and manages lists of reminders and ToDo's. ReminderFox makes sure you remember all of your important dates via easy-to-use lists, alerts, and alarms, right in your browser without the need for a separate calendar program.
Adds private tabs.
Add-on for Thunderbird that replaces the built-in notifications with OS native ones. It supports most Linux Desktop Environments as well as Windows 8.1/10.
EDS Calendar Integration Requires Restart
Integrates calendars events with Gnome clock applet
Plugin may hang on Fedora.
As a workaround uninstall evolution-ews.
Zombie Keys (Multilanguage Keyboard) Requires Restart
Enter accents, diacritics, diaeresis, umlauts, ligatures etc. with keyboards of various countries (us,uk,ie,fr,it,ru,de,sv) - via easy to remember shortcuts or menu. Also supports all textboxes of the application (such as search, filters).
QuickPasswords Requires Restart
Retrieve your Passwords the quick way! Never retype or display your secure passwords on screen anymore - put the password where you need it - the login form or the clipboard.
Now also includes SSO change (multi-domain pw) and Backup + Restore.
Mail Redirect Requires Restart
Allow to redirect (a.k.a. "remail") mail messages to other recipients.
Header Tools Lite Requires Restart
Allows to modify the header and the source of messages
Tategaki Requires Restart
Tategaki allows vertical writing-mode on mail compose window.
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.