Welcome to Thunderbird Add-ons.
Add extra features and styles to make Thunderbird your own.Close
Sensitivity Header 0.2 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.
This add-on has been marked as experimental by its developers
About this Add-on
While adding this header does not directly add any security to the message, the header can be interpreted by some MTA/MUAs such that the message is treated differently while in transit, or when viewed by the recipient:
- e.g. MS Outlook/Exchange: Can be set so that confidential/personal messages are unable to be read by the recipient's delegated users; A warning can be displayed before the message is forwareded; Displays an advisory message above content.
- e.g. Some versions of Symantec PGP in corporate set-ups can automatically encrypt the outgoing message if leaving the corporate network, or redirect it to a secure corporate webmail page (with an automated notification email to the recipient to collect it there).
When re-opening a draft message where a sensitivity was set, the previous value is not currently retained. Similarly, when forwarding or replying to a message, the sensitivity value from the original message is not currently retained. As such, please make sure to select the correct sensitivity before sending your messages - if you add the toolbar item, this is always visible when composing. I hope to find a fix for these issues in a future version.
This addon does not currently show an indicator for received messages yet - In future versions of this addon, I may add some kind of (optional) banner above the message when the header is set to Personal/Private/Confidential. In the meantime, if the header has been set on any message, it will be visible if 'View Menu -> Headers -> All' is ticked.
If you're familiar with Thunderbird addon development and want to help out or add translations, please get in touch via https://github.com/BobSoft3000/tb-sensitivity-header/.