Release Notes

Thunderbird will now display a message when an upgrade migration task is taking a long time to complete

es-MX localized build now available

What's new link displayed in About: dialog

Profile Import/Export UI refreshed and moved to a tab

Commandline tools now included for OpenPGP debugging

Thunderbird may now be built with OpenPGP support and a system librnp

Added menu option to permanently decrypt OpenPGP encrypted messages to a folder

OpenPGP: Public keys from email attachments and autocrypt headers now cached for future use

Expired OpenPGP recipient keys now indicated in compose window

OpenPGP Key Assistant enabled by default

OpenPGP Key Properties now supports refreshing keys from key server

Spaces vertical toolbar for easier in-app navigation

Compose toolbar button for OpenPGP & S/MIME signing available via "Customize Toolbar"

"Select all addresses" now supported from composer pill context menu

Multiple active spelling dictionaries now supported in compose window

Add dictionaries item added to Spelling button in compose window

Added config option to more aggressively warn sender about having many public recipients to an email (mail.compose.warn_public_recipients.aggressive)

Exporting current profile now supported on importing tab

Back/Forward keyboard shortcuts added to Addon Manager

New Address Book UI and significant backend overhaul

Importing sqlite address books now supported

Importing addressbooks via CSV file now supports semi-colon (;) delimited files

Opening a news:// URL now works if an account is not configured for that news server

Google Talk chat accounts now support logging in with OAuth2

Matrix chat support enabled by default. This is a beta feature.

Printing using the system dialog without preview now supported; Set print.prefer_system_dialog to true

Removing events from a calendar now prompts for confirmation

Upcoming events in the Today Pane show how far away they are

Icons now displayed on recurring events and modified events within a recurring series

SMTP client will now ignore socket errors after QUIT command is sen

Javascript POP implementation enabled by default

Buttons on "Update Failed" popup now open Beta and Release specific pages on Thunderbird website

Replace "About Junk Mail" dialog with a link to the support page

[macOS] Account settings moved to application menu

New profiles will default to using "Threaded" message view

"Discover OpenPGP Key" context menu item is no longer displayed when a key is already available

Duplicated OpenPGP encrypted attachments were shown when display-attachments-inline was enabled

Replaced Security compose toolbar button with Encryption toggle and Encryption options buttons

OpenPGP dialog for key "acceptance per email" now displayed in more circumstances

OpenPGP Key Manager dialog layout improvements

Writing OpenPGP keyring data will block Thunderbird shutdown to prevent data loss

When automatically attaching OpenPGP keys to emails, Thunderbird will strip key certificates

A notification bar in the compose window will be displayed if encryption is possible but not enabled

Inline attachment filenames now sent without data-uri encoding

Per-recipient and per-domain email format preferences removed; Sending options moved to Compose Settings

Thunderbird can now be used without setting up a mail account

NNTP account set up moved to its own wizard; "Other accounts" wizard removed

Account Manager UI updated

Email account provisioner moved to a tab

Link to create a new email address in Account Setup now hidden if "Email address" contains a value

Addon Search will no longer display addons that are incompatible

Searching from the Themes page of Addon Manager will now limit search results to only include themes

Additional fields for download limits, expiration, and password protection added to FileLink template

FileLink will check the provider for sufficient space before uploading

"PreferMailFormat" property removed from addressbook

Address book contact data is now stored in the vCard format. The change isn't backwards-compatible; backups are stored in the profile directory.

Default install directory for Thunderbird Beta changed to not conflict with release versions

Tab icons updated

Message Header toolbar buttons will not display a border when set to show icons only

New message detection for non-INBOX IMAP folders improved

New Javascript NNTP implementation enabled by default; Set mailnews.nntp.jsmodule to false to disable

Preference for OTR encrypted conversation logging moved to Protocol settings

Thunderbird will not try to use OTR Chat encryption if the protocol supports native encryption

Invitations to IRC and XMPP chat rooms will now prompt the user if they would like to join

Today Pane UI refreshed

Thunderbird will not support "Secondly" or "Minutely" recurring calendar events

Default action of Edit button in recurring event dialog changed to display submenu

Support for importing and exporting calendars from Outlook CSV format was removed

Thunderbird will now delay refreshing cached calendars at start-up

Javascript Ical parser (ical.js) enabled by default

Opening "cid:" links failed

Message download progress was calculated incorrectly

Ctrl+mouse wheel did not zoom in the message source window

Open message in containing folder did not work for standalone windows

Multi-message view was not fully scrollable

Messages did not reload in all open windows after Junk status was changed

Detached attachments were opened from a temporary copy instead of the selected save location

IMAP folder subscription changes on servers using OAuth2 authentication were not reflected in folder pane until Thunderbird was restarted

Improved error reporting for external GnuPG configurations

Incorrect OpenPGP preferences were used for secondary identities

Adding an expiry date to an OpenPGP key that did not have one was not possible

UI showed old OpenPGP key expiry date after changing it

Importing large OpenPGP key files failed

OpenPGP "Repair Message" button did not work with some emails

Importing OpenPGP public keys without a blank line following the header failed

Dragging and dropping multiple email attachments between windows did not always copy all attachments

Attachment bar in message compose window was not keyboard accessible

Triggering recipient pill creation in the compose window incorrectly used the entire field as input

Compose notification bars were not easily accessible via keyboard

"Save message" confirmation dialog buttons were not navigable using arrow keys

Focus jumped in compose window when closing the contacts sidebar

Save dialog was incorrectly shown when closing empty composer windows

Incorrect access key used for File->New->Message menu item

Changing focus in the compose window with multiple recipient pills selected did not always deselect the pills

Sending a message with non-ascii characters in recipient local parts failed unexpectedly when the server did not support SMTPUTF8

LDAP Autoconfig could block Thunderbird startup

Improvements to the Import/Export feature

Configuring multiple SMTP accounts using the same server was not possible

Empty Trash on Exit did not work with IMAP accounts using OAuth2 authentication

IMAP server hostname changes were not reflected in Folder Properties dialog

Addons automatically updated when Thunderbird updated despite Addon updates being turned off

Message size calculations incorrectly included FileLink attachments

After converting a FileLink attachment back to an e-mail attachment, the privacy notification persisted

A failed FileLink provider change removed the attachment completely

Subscribing to CardDAV address books from Account Setup tab did not subscribe to all selected address books

Adding CardDAV address books failed if an addon-provided address book was present

Messages with Message-Id headers longer than 332 characters could not be forwarded

SMTP send progress bar could trigger high CPU usage when the server connection failed

Improved POP server authentication detection during Account Setup

News folders did not display biff indicator

IMAP flag changes from another client were not seen after some inactivity

Recipients were not de-duplicated before sending, leading to sending errors

Chat conversations' context menu did not recognize links

Chat username splitting in the account wizard did not work after changing protocols

Removing obsolete proprietary chat accounts did not work

OTR encrypted chat did not work on FreeBSD

Event edit toolbar button was not disabled when an invitation was selected

Event view headers and content were not lined up consistently for RTL locales

Mini-month views did not properly update at midnight

Some labels in Calendar were displayed in multiple languages

Thunderbird permitted inline editing of read-only event titles

Calendar view reloaded when switching tabs

It was possible to create annual calendar events with invalid days

Detection of attached vCalendar files improved

Reminders for events created by another user could not be closed

MS Teams meeting event descriptions were unreadable when stored on Google Calendar

Adding a Google calendar with a non-gmail or googlemail e-mail address failed

Accepting a recurrence exception to an event accepted event associated with the original recurring event rather than the exception

Various security fixes