Release Notes

Thunderbird Desktop

Version 115.0 | Released July 11, 2023

Check out the notes below for this version of Thunderbird. As always, you’re encouraged to tell us what you think, or file a bug in Bugzilla.

Thunderbird version 115.0 is only offered as direct download from thunderbird.net and not as an upgrade from Thunderbird version 102 or earlier. A future release will provide updates from earlier versions.

For more on all the new features in Thunderbird 115, see What’s New in Thunderbird 115.

System Requirements: Details

  • Windows: Windows 7 or later
  • Mac: macOS 10.12 or later
  • Linux: GTK+ 3.14 or higher

What’s New

new

Supernova UI with updated 3-Pane window with updated folder, message list, and message display panes; updated Quick Filter, Calendar and Address Book with new Vertical View, Unified Toolbar.

new

New folders are now added to virtual parent folders and saved searches automatically

new

Thunderbird can now open external .eml files in a tab

new

"Move To" and "Copy To" actions added to Folder context menu

new

Thunderbird now supports HKP keyservers that return one key per email address

new

Thunderbird can now upload OpenPGP public keys to VKS and HKP keyservers

new

Thunderbird now notifies the user if a message includes nested encryption, and allows viewing each encrypted part of the message

new

OpenPGP signature dates are now shown for signed messages

new

OpenPGP candidate keys can now be discovered and imported from GnuPG keyring, if external GnuPG is enabled

new

Candidate OpenPGP keys are now automatically discovered from GnuPG keyring, if external GnuPG is enabled

new

Thunderbird now supports option to always send public key with autocrypt header

new

Automatic enabling/disabling of encryption can now be enabled through UI

new

User-defined OpenPGP passphrases now supported

new

OpenPGP signature filenames now always end in ".asc"

new

Thunderbird can now open OpenPGP Key Manager dialog from commandline using "-keymanager" option

new

Using CSS styles in composer enabled; set editor.use_css to true

new

Thunderbird now supports OAuth2 for Fastmail

new

Thunderbird now includes the option to send a minimal user agent header, or no header at all

new

Thunderbird will now send a minimal user-agent header by default

new

Searching for "about:config" in Settings now finds "about:config"

new

Added option to always show system tray icon on Windows

new

Address book cards now support phone and fax number links

new

Thunderbird now includes a "app.update.log.file" preference to enable logging of updates

new

Search Engines Enterprise Policy added

new

Thunderbird can now individually reload remote calendars

new

Added "Show tasks in calendar" option to Calendar Control menu

new

Setting to use OS-configure timezone added

What’s Changed

changed

Office365 accounts using password authentication will auto-migrate to OAuth2

changed

Thunderbird now uses a non-private browser for OAuth login, allowing login to Microsoft Office 365 with Conditional Access Policies enabled

changed

Thunderbird now opens all external links from 3-pane window in the user's browser

changed

HTML emails are now rendered in Standards mode

changed

Link to "introduction to e2e encryption" article updated

changed

OpenPGP messages now default to using combined signing and encryption

changed

Thunderbird now displays a warning when trying to send a message if the current OpenPGP key is expired

changed

S/MIME signatures using the MD5 or SHA1 hash algorithms are now rejected

changed

Extension "Options" button now disabled rather than hidden when an extension is disabled or has no options

changed

Support for additional fields added to Address Book

changed

Search box in horizontal Address book layout moved to the left

changed

Updated Thunderbird color palette

changed

C++ NNTP implementation removed

changed

POP C++ implementation removed

changed

Thunderbird will reuse SMTP connections when sending multiple messages

changed

Names for empty Matrix rooms can now be localized

changed

Next and Previous Calendar menu items in Go menu now hidden until Calendar is activated

What’s Fixed

fixed

Users using Microsoft business email services may not be able to login due to deprecation of basic auth for Exchange

fixed

Spell Check dialog did not open when selected text included a line break or new paragraph

fixed

Autocomplete functionality in the composer failed under some circumstances

fixed

Some emojis displayed incorrectly when added to a message; added angry face emoji

fixed

Unicode character set information was not included in message header when composing message via "Forward" or "Edit as new message"

fixed

Forwarding messages as attachment via drag-and-drop did not follow preference to add file extension to attachment file names

fixed

Subject lines longer than the available title bar width in "New Message" window displaced title bar buttons on macOS

fixed

Opening internal document links in PDF files opened a new tab with a copy of the document instead of scrolling to the linked location

fixed

"Gentle smile" plain text ;) emoticons were incorrectly rendered as "Strong smile"/"Laugh"

fixed

Files saved via Save Attachment did not appear under Saved Files

fixed

Buttons in message header (Reply, Forward, etc) were not keyboard accessible

fixed

Drop-down buttons in message header could not be activated using Enter or Space

fixed

A "Learn More" link was missing from the "Do not track" option in "Privacy & Security" Settings

fixed

"Empty Trash on Exit" was not always triggered when message quarantine was enabled

fixed

Emails in Yahoo and AOL accounts were incorrectly classified as Junk

fixed

"Run Junk Mail Controls" did not work

fixed

HTML signature containing image hosted on a web server changed source URL of image to local filename

fixed

Changing the default search engine did not persist after closing "Settings" tab

fixed

About dialog display of distribution.ini information restored

fixed

All menu items in "Help" menu were disabled after sending a message on macOS

fixed

An empty dialog message was displayed when sending an OpenPGP signed email with a key that could not be found

fixed

When reopening OpenPGP-encrypted drafts/templates after closing the compose window, Thunderbird did not restore the subject line

fixed

OpenPGP key verification only used first From field for emails with multiple From fields

fixed

Encrypted attachment was displayed on OpenPGP encrypted messages, even if no attachment was available

fixed

When disk is full, partial data left behind by IMAP/News folder compaction was not deleted

fixed

Thunderbird did not decrypt OpenPGP messages with an additional outer signature layer

fixed

(was: old subject) was not removed from message subject on reply with OpenPGP enabled

fixed

Context menu could not be opened in OpenPGP key manager using keyboard

fixed

"Passphrase" tab of Key Manager was incorrectly shown for public keys

fixed

Upstream RNP version numbers now recognized as official in about:support

fixed

Expired OpenPGP keys were shown as "Not found" in Account Settings

fixed

Layout and styling issues with OpenPGP dialogs

fixed

Encrypted messages could not be decrypted using revoked OpenPGP key

fixed

Thunderbird no longer requires a primary secret key to be available when signing messages

fixed

Thunderbird was unable to send signed messages with OpenPGP subkey

fixed

OpenPGP Message Security dialog was sometimes positioned incorrectly

fixed

Messages signed with revoked S/MIME certificates were displayed as correctly signed

fixed

Auto-enabling and auto-disabling of E2E encryption did not behave as expected under certain circumstances

fixed

Automatic detection of SSL/TLS connections during account creation was broken

fixed

Canceling account setup during verification prevents account from being added again

fixed

Manually-configured accounts were silently deleted after pressing "Finish" on Account Setup page

fixed

Loss of messages would occur if messages were moved from POP/Local to IMAP while offline, followed by going online

fixed

POP3 messages were deleted from server when attachments were detached from the message in Thunderbird

fixed

Thunderbird sometimes did not synchronize offline IMAP folders after a restart

fixed

IMAP autosync sometimes stopped after restoring computer from sleep or hibernation

fixed

Loss of connection while moving multiple messages to an IMAP server could result in duplicate messages on source and destination servers

fixed

Thunderbird did not check to see if "UTF8=ACCEPT" is supported by IMAP server before enabling it

fixed

Copying IMAP folders between servers failed when source folder was previously copied and deleted from destination server, and destination server is set to only mark items as deleted

fixed

IMAP folder "Compact" action did not wait for expunge operation to complete prior to compaction

fixed

Progress dialog did not appear for manual retry of saving IMAP messages to Sent, Draft, or Template folders

fixed

Embedded images now include filename and extension in header if none is included

fixed

Messages could not be sent through some SMTP servers due to unhandled formatting of username prompt

fixed

NNTP message streaming did not work, resulting in uncaught errors

fixed

NNTP connection was not closed immediately if authentication dialog was canceled

fixed

Search on Server only returned results for articles on the server that had already been downloaded

fixed

Status bar did not update when NNTP server connected/disconnected

fixed

Adding too many terms to an Advanced Address Book Search caused the list view to overflow without scrolling, making overflowed terms inaccessible

fixed

Contact pane was not resizable when editing a contact

fixed

Creating a new contact was possible while editing an existing contact, with data loss of unsaved changes possible

fixed

Deleting or moving a contact from one address book to another did not update the list of cards

fixed

CardDAV discovery now uses preset location if MX records point to Google

fixed

Long lists of chat conversations could not be fully viewed or scrolled

fixed

Thunderbird incorrectly addressed all XMPP pings to the connected XMPP server, rather than the originator of the ping

fixed

Duplicate Matrix clients were created under certain circumstances, resulting in duplicate messages under the same account

fixed

Encryption of new Matrix direct messages was not detected correctly

fixed

Matrix direct message rooms were duplicated under certain circumstances

fixed

Events were not shown in the correct week if week start was not set to Monday

fixed

When creating a new event, the organizer was not automatically added to the event

fixed

Calendar time-of-day indicator increasingly drifted ahead of current time when staying on calendar tab without switching to other tabs

fixed

Multi-part messages could not be converted to tasks

fixed

Editing events via right click menu failed to save changes

fixed

Task previews did not show HTML formatting

fixed

Attendees in Event Summary dialog were not selectable

fixed

After restarting Thunderbird, all-day to-do tasks changed to tasks set at midnight of the same day

fixed

Calendars with a name containing a slash could not be exported without first being renamed

fixed

Extra linebreaks in Google Calendar event descriptions removed

fixed

Modifying events in locally-hosted ICS calendars sometimes led to data loss

fixed

Local calendars with custom timezone definitions unable to sync with CalDAV servers

Learn What’s Next

Thunderbird keeps getting better. Subscribe to our newsletter and follow us on social media to stay informed.