Add-ons
Privacy and Security
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Reply All Control
Requires Restart
Allows you to disable the ability to use Reply All when your email address does not appear in the To: or CC: fields. This usually means you've been BCC'd and Reply All might reveal the sender's sinister plot.
ReplyAsOriginalRecipientUp
When you reply to a mail sent to your personalized address (postfix/qmail/gmail extensions) such as john.doe+contactname@example.com, "From:" is replaced by your personalized address rather than your simple address.
Report Phishing
Requires Restart
Report Phishing is an Add-on for Thunderbird that makes it easy to report phishing emails. Reported emails are analyzed for malicious links that are then sent to security companies for blocking and mitigation.
Rspamd-spamness
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
Safelink removal
Replace URLs which have been rewritten by Office 365 Advanced Threat Protection with the original URL.
Safelinks Cleanup
Cleans up Outlook’s “safelinks” tracking.
Minimal code to allow for easy auditing of the add-on. The only code is:
https://github.com/Cimbali/safelinks-cleanup/blob/main/src/background.js
Saved Password Editor
Requires Restart
Adds the ability to create and edit entries in the password manager.
SecondOpinion
Requires Restart
This extension implements a convenient way to check and upload attachments against VirusTotal.com
Secure Addressing
Requires Restart
This add-on provides features to avoid sending emails to wrong addresses. Key features are a confirmation window of recipient's addresses upon sending, name and affiliation look up at mail composition and main windows, and safe auto completion.
Security Settings from Address Book
Requires Restart
Sets message security (sign/encrypt) when sending or saving messages based on recipients' address book entry's field "Custom1".
Sender Address Columns
Requires Restart
Adds optional columns to the Thread Pane to allow sorting email messages by:
* Full sender address -- e.g. "someone@example.com"
* Sender's domain -- e.g. "example.com"
* Sender's local part -- e.g. "someone"
* Sender's TLD -- e.g. ".com"
Sender Verification Anti-Phishing Extension
Requires Restart
Protects you from phishing attacks by verifying the From: address domain name of emails as you read them. Sender Policy Framework (SPF) and DNS-based reputation lists are used.
Sensitive Attachment Guard
Requires Restart
A Thunderbird add-on censor sensitive attachments (currently Microsoft Office documents) from being sent to unintended recipients.
Sensitivity Header
Requires Restart
Implement the "Sensitivity" header for outgoing messages (described in RFC 4021 section 2.1.55).
This allows the user to select Private / Personal / Company-Confidential (or none) for an outgoing message.
No longer maintained: See below.
Sensitivity Header + SPX
Requires Restart
Implement the "Sensitivity" header for outgoing messages (described in RFC 4021 section 2.1.55).
Forked from another add-on developed by ff_bob, added SPX header for Sophos security appliances
Show Password On Input
Requires Restart
Gives an option to show the master password on input
Signal Spam
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).
Silent Block
SmartProxy
SmartProxy is a smart automatic proxy switcher that will automatically enable/disable proxy for the sites you visit, based on customizable rules.
To create your own collections, you must have a Mozilla Add-ons account.
