Thunderbird Add-on "Correct Identity" (v2.4.x)

This add-on version works with Thunderbird versions >= 102.0

Version Support History:
Last version v2.3.2 supported Thunderbird version >= 91.0
Version v2.1.1 supported Thunderbird version >= 91.0
Version v2.0.1 supported Thunderbird version >= 78.0

It's a perfect alternative/continuation

• of the original (version 1.x.x) Correct Identity
• to Flexible Identity

which don't work anymore because Thunderbird switched to new Plugin API framework called WebExtension.

Check also the built-in features of Thunderbird which also evolve over time.

The add-on comes in 5 different languages. Here is a screenshot of the settings window:

Using Correct Identity

This add-on helps to always use the correct "from" email identity when replying to messages or composing new messages.

The configuration reflects the Thunderbird concept of "accounts" and "identities":

• accounts: are the mailboxes where emails arrive and associated servers used to send emails
• identities: are the email addresses available for composing emails. Typically the main email address of the accounts plus the configured aliases. Each identity is bound to a specific account.

The typical configurations use lists of "regular expressions". In the simplest from this could be complete email addresses or parts of email addresses.

Features

• Choose the initial "from" identity when composing a new email
• Choose the "from" identity when replying to a message
  • based on the original recipients of the replied-to message
  • NEW in 2.4.x: based on addressbook entries
  • based on non-standard SMTP header fields of the replied-to message (new feature: "Advanced: Additional mail headers")
• Automatically change the "from" identity when addressing specific recipients
• Warn if specific recipients are included in a email send from a specific identity

NEW in 2.4.x: Addressbook Match

Instead of using individual match entries, also a complete addressbook can be checked for a match. As an example you can add the following line to the text field: addressbook="My Private Address Book"

The string in quotes is the name of the address book as given in the address book pane. Can be copied from address book properties.

Advanced: Additional mail headers

Email header fields are keywords in the SMTP (Simple Mail Transfer Protocol) message. E.g. "To" identifies the email recipient. Beyond those standard headers, some email providers use vendor-specific headers e.g. to identify the original recipient of a forwarded message. Some known headers are:

• Received
• Delivered-To
• X-Delivered-to
• X-Apparently-To
• X-Resolved-to
• X-Mail-from

To check if your email provider uses such a header field to transport an address you are interested in, browse the source of the message (e.g. Ctrl+U in Thunderbird message view). Add the found header name (optionally with an occurrence index) to the configuration. E.g. Received#3 uses the third "received:" header line to find a potential match.

The found header lines are prepended to the normal "recipients" e.g. from "To:" and used to find a matching "from" identity. The first match is taken. So the sequence of the header fields in the configuration defines the search priority. Header fields that are not present in the mail are ignored.

Configuration Shortcut

When this add-on is installed, a small icon "Ci" appears in the Thunderbird toolbar. This icon provides a shortcut to the add-on configuration page.

Installation

The github repository dennisverspuij/tb-correctidentity holds the latest (development) version of the add-on. The version available at Thunderbird Add-ons site will be updated regularly.

Steps for installation (local build):

1. Download this repository
2. In the repository folder, execute ./make_xpi.sh to create an .xpi file
3. Open Thunderbird, go to /Add-ons/, and click /Install add-on from file/
4. Choose the .xpi file in the repository folder

The .xpi files come in two flavours:

• correct_identity_vX.Y.Z.xpi is a version which could (in theory) be released to the official Thunderbird add-on store
• correct_identity_vX.Y.Z_dev.xpi has the same content, but has no limitation on the highest supported Thunderbird version ("strict_max_version"). Use this version to test this add-on on newer Thunderbird versions not known at date of the add-on release. (Feedback welcome).

The add-on can now be configured in the add-on manager tab.

Alternatively you can directly download an .xpi file from the "Releases" section.

Development & Contributing

1. Fork this repo and download it with git pull
2. Call ./make_xpi.sh in the repo
3. In Thunderbird, Menu /Extras/ → /Development Tools/ → /Debug Add-ons/
4. /Load temporary Add-on/ and select the .xpi file
5. Then you can press /Reload/
6. …
7. Send us a pull request!

Note that you have to generate a .xpi file with the same name whenever you change the source code. You can use a file watcher like inotify to automate this.

In Menu /Extras/ → /Development Tools/ you'll also find a dev console and more debugging tools.

Acknowledgment

Many thanks to @dennisverspuij, the original author , and to @ldreier who ported this add-on to Thunderbird 67!

Trivia

Before this fork:

Here is the old version of Correct Identity which doesn't work on Thunderbird versions > 67.