Privacy and Security
Paranoia Requires Restart
Check if your emails arrived TLS-encrypted (and which corporations were able to read it nevertheless)
Signal Spam Requires Restart
Add simple functions to report spams or phishing to Signal Spam by one click.
The add-on will also alert you if you open a fraudulent e-mail (phishing).
Soapy Requires Restart
Bypasses DNS-based censorship
NOTE: This was created as a SOPA protest in 2012. This does not work anymore for most sites. Use Tor instead.
Classic Password Editor Requires Restart
Adds the ability to create and edit entries in the password manager.
MDN Extended Requires Restart
Allows the recipient of a message to send a return receipt (MDN: Message Disposition Notification) on message deletion. This addon is usefull for better experience with Notification Viewer addon.
Key Manager Requires Restart
KeyManager Tool: Firefox Add-on for Key Generation, Certificate Enrollment, CRL Signing, and Identity and Authority Delegation
Disable about:config Requires Restart
Disable about:config feature of Firefox and Thunderbird.
Identity Select Requires Restart
This extension allows you to choose the identity of your new email from a popup menu directly from the Write button. This feature behaves in a similar manner as the Get Mail pulldown menu. In addition, the default behavior of the Write button is...
Minimum and fast URL blocker.
DSN Settings Requires Restart
Adds user interface settings for Delivery Status Notification (DSN) requests. This addon is usefull for settings for Delivery Notification request and better experience with Notification Viewer addon.
Great DANE Requires Restart
Retrieve DANE S/MIME Certificates for Encryption/Signing.
This extension enables users to automatically retrieve S/MIME certificates using the Great DANE Engine (https://github.com/grierforensics/Great-DANE-Engine).
KeePass Helper Requires Restart
Adds a hostname, URL, or email account ID to the application's window name (e.g., that of Firefox or Thunderbird) to make it recognizable to password manager utilities like KeePass.
KDE5 Wallet password integration Requires Restart
This extension enable passwords and form logins to be stored in KDE5 Wallet
eelpout Requires Restart
The anti-phish. An informative phishing detection...
Clear IMAP Local Cache Requires Restart
Clears IMAP local cache on startup.
CapsKiller Requires Restart
Caps Killer is a protection against newbies using caps in their mails.
Mailsleuth Requires Restart
Mailsleuth is a add-on for Thunderbird that provides you a full email header analysis of any email in your Inbox. This add-on is designed to provide a report on the email headers on any email you choose from your inbox. MAJOR updates for Feb 2013!
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.
Deny resource:// access to Web content: We fill the hole to defend against fingerprinting. Very important to Firefox privacy. A direct workaround for bugzil.la/863246
S/MIME Security for Multiple Identities Requires Restart
Adds S/MIME Security configuration to the multiple identities dialog.
Meanwhile this feater has been integrated into Thunderbird 3