New Update Mozilla Thunderbird (updates and discussion)

silversurfer

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Thunderbird version 91.0 is only offered as direct download from thunderbird.net and not as an upgrade from Thunderbird version 78 or earlier. A future release will provide updates from earlier versions.

System Requirements: Details
  • Windows: Windows 7 or later
  • macOS: macOS 10.12 or later (macOS 11.0 for Silicon)
  • Linux: GTK+ 3.14 or higher
 
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silversurfer

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Thunderbird 91 is available as a manual upgrade​

Thunderbird 91 is a new major version, which introduces new features and changes. The email client is the first to support Apple Silicon CPUs natively, which benefits Mac OS users.

The program makes use of multiple processes by default now, similarly to how Firefox introduced support for the feature a long time ago.

The email account setup process has been improved in the new version of Thunderbird. The email client supports CardDAV address books now, and will detect these automatically based on the email address the user provides. Similarly, remote calendars will be detected automatically to streamline the setup process.

If you set up a Gmail account, Thunderbird will detect the address book and calendar, if available, to suggest to import the data right away. [...]
 

silversurfer

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Thunderbird Version 91.0.2, first offered to channel users on August 23, 2021

NEW​

  • Tags are now colored in mail filter editor
  • Preference for disabling the unread message count badge on Windows taskbar icon added: mail.biff.show_badge

CHANGED​

  • Context menu items related to OpenPGP and attachments are now hidden when not applicable

FIXED​

  • Creating a new account with manual setup failed
  • Recipient autocomplete always preferred the primary email address for a contact
  • LDAP performance improvements
  • Extensions listed on the Recommended Addons did not have a clear way to view details in a browser
  • Status checkmark on View > Calendar > Calendar Pane > Show Calendar Pane was reversed
  • mid: URLs in calendar invites did not open the linked mail message
  • Various theme and UX fixes


 
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silversurfer

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Thunderbird Version 91.0.3, first offered to channel users on August 26, 2021

FIXED​

  • Folder icons could be overridden by linked favicons in HTML messages
  • Unified folders showed no messages when underlying folders were removed
  • Folder pane toolbar did not always persist after restarting Thunderbird
  • Compose window attachment pane did not close when disabling signing of an OpenPGP message
  • Using "Reply to List" with some list emails incorrectly opened a "no-reply" warning
  • Unread message count badge on Windows tray icon did not update after moving messages to the Junk folder
  • Account setup UX issues with Exchange autodiscover
  • Account settings did not display non-UTF-8 server descriptions correctly
  • Thunderbird sometimes sent an unnecessary "SMTPUTF8", causing some servers to reject mail
  • No mouseover pop was displayed with event details for non-all-day events in the Today Pane
  • Filtering tasks in the Today Pane did not work
  • Email based event scheduling displayed the date and time in a format unreadable by humans


 
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Gandalf_The_Grey

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The developers of the Thunderbird email client have already released another bug fix update on August 26, 2021 (version 91 is still dewy, on August 17, 2021 there was a maintenance and security update to version 91.0.1 and on 8/23/2021 version 91.0.2). Apparently there is no real testing going on anymore.
 

silversurfer

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Thunderbird Version 91.1.0 (first offered to channel users on September 7, 2021)

Changed​

  • VCard attachments now sent with "text/vcard" instead of "text/x-vcard"

Fixed​

  • Thunderbird registered Accessibility Handlers using same GUIDs as Firefox, causing performance issues for NVDA users
  • Focus lost when reordering accounts by keyboard in the Account Manager
  • Account setup did not use provider display name for setting up calendars
  • Various theme and UX fixes
  • Various security fixes
 

silversurfer

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Thunderbird Version 91.1.1 (first offered to channel users on September 16, 2021)
New:
  • Menu item for disabling subject encryption for a single message added
Changed:
  • Printing messages that are not currently displayed is no longer supported, including printing multiple messages at once
Fixed:
  • Buttons on compose window dialogs did not have a visual indication of focus
  • Dropdown fields in message compose window were unreadable on Windows 7 with a dark theme
  • Multiple bulk mail notification warnings were displayed
  • Enabled/Disabled state of message filters did not persist as expected
  • Printing a message did not print a list of its attachments
  • Images attached from a web page were not sent as expected
  • OpenPGP public key was attached multiple times when forwading a message
  • Windows tray icon disappeared if Thunderbird was started by a shortcut with "Run" set to "Minimized"
  • Windows tray message count badge displayed the "unread" count instead of the "new" message count
  • Some downstream Thunderbird builds were incorrectly checking addons for a signature, causing all addons to be disabled
  • Addressbooks set up with autoconfig showed no search results
  • Various CardDAV setup and auto-detection fixes
  • Dates (such as birthday) stored in contacts may display the wrong date; a one-time manual fix may be needed for dates that are incorrect.
  • Attached VCards displayed as plain text when an email was HTML formatted
  • Mailing list names with non-ASCII characters incorrectly displayed with an error
  • LDAP directories were not searched for matches when adding recipients to an email
  • Clicking "Connect to an LDAP address book" in account setup opened CardDAV setup dialog
  • LDAP address books using Kerberos/GSS-API authentication did not authenticate
  • LDAP search queries containing non-ASCII characters produced no results
  • IRC server connections did not automatically retry after a timeout
  • Calendar event editor did not honor mail.spellcheck.inline
 

silversurfer

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Thunderbird Version 91.1.2 (first offered to channel users on September 28, 2021)

CHANGED:​

  • Thunderbird will now warn if an S/MIME encrypted message includes BCC recipients

FIXED:​

  • Message Security popup did not display all recipients due a missing scrollbar
  • Delivery Status Notifications were only shown for the first recipient
  • Composing a message from a template with attachments failed due to a temporary file being removed
  • Attachment sizes were no longer included on printed emails
  • A message sent with multiple attachments sometimes only sent one
  • Thunderbird sometimes attached the wrong messages when forwarding multiple messages by attachment
  • Thunderbird did not re-prompt for an SMTP username if one was not provided
  • Messages with BCC recipients that were held in the Outbox did not retain the BCC header when moved to the Sent folder
  • Thunderbird displayed reminders for events that were cancelled or declined
  • New Feed Account dialog did not honor dark mode
 

silversurfer

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Thunderbird Version 91.2.0 (first offered to channel users on October 7, 2021)

Changed​

  • Saving a single message as .eml now uses a unique filename

Fixed​

  • New mail notifications did not properly take subfolders into account
  • Decrypting binary attachments when using an external GnuPG configuration failed
  • Account name fields in the account manager were not big enough for long names
  • LDAP searches using an extensibleMatch filter returned no results
  • Read-only CalDAV calendars and CardDAV address books were not detected
  • Multipart messages containing a calendar invite did not display any of the human-readable alternatives
  • Some calendar days were displayed incorrectly or duplicated (eg. two "29th" days of a particular month)
  • Phantom event was shown at the end of each day in Calendar week view
  • Various security fixes
 

silversurfer

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Any Thunderbird 78.x installation will be upgraded to the latest version of Thunderbird 91, provided that automatic updates is enabled.
Thunderbird 78.15.0 is the last release for version 78 of Thunderbird. New updates, security or otherwise, won't be released anymore for the client.
 

silversurfer

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Thunderbird Version 91.2.1 (first offered to channel users on October 21, 2021)

New​

  • Preference added to disable automatic pausing RSS feed updates after a fetch failure

Fixed​

  • Recipeint address pills in an error state could incorrectly merge with mailing list pills when expanding the list
  • BCC-only messages could not be sent from the Outbox
  • Default DSN request was not set when using "Edit as New Message"
  • Vertical scrollbar in "Conversations" chat panel did not work correctly
  • Chat account "Advanced Options" dialog had no clickable buttons on macOS
  • RSS feed attachments could not be saved
  • Public ICS calendars served with an incorrect Content-Type could not be added
  • Setting a CalDAV calendar to manually update had no effect
  • CalDAV calendars set to read-only became writable after restarting Thunderbird
  • Saving a copy of a calendar invite (More -> Save As Copy) did not work
  • Events in the first or last week of a month were not always printed when printing a month view
  • Accessibility improvements; clearer display of area of focus
  • Various theme improvements, HiDPI improvements
  • "Attachments" menu panels for attached files were empty
  • Stability improvements
 

Gandalf_The_Grey

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Thunderbird Version 91.3.0, first offered to channel users on November 3, 2021

FIXED​

  • Default mail headers were set incorrectly when the value contained a colon
  • Thunderbird did not send the QUIT command when closing an SMTP connection
  • Mail tabs could not be closed using the context menu
  • "Print" context menu was still shown when no message pane was displayed
  • Windows tray icon did not reappear after restarting Windows Explorer
  • Compose window attachment drag and drop fixes
  • Various macOS stability improvements
  • Drag and Drop area for file attachments on Windows was incorrect
  • CardDAV address books without a name did not work
  • Thunderbird tried to refresh disabled and manual-only calendars when the network state changed from offline to online
  • Various Calendar event dialog fixes
  • Various security fixes
 

silversurfer

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Mozilla released Thunderbird 91.3 to fix several high-impact vulnerabilities that can cause a denial of service, spoof the origin, bypass security policies, and allow arbitrary code execution.
Triggering most of the newly discovered bugs requires a user to open a specially crafted website in a browsing context, so the exploitation is relatively simple.
 

silversurfer

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Thunderbird Version 91.3.1 first offered to channel users on November 15, 2021
CHANGED:
  • OpenPGP public keys will no longer count as an attachment in the message list
  • Adding a search engine via URL now supported
  • FileLink messages' template updated; Thunderbird advertisement removed
  • After an update, Thunderbird will now check installed addons for updates
FIXED:
  • New mail popups were displayed while running full screen applications
  • Messages received with non-standard "koi8r" encoding were not supported
  • Various macOS stability improvements
  • PDF attachments opened in Firefox while composing an email
  • Addons were disabled when "Offline Settings" were set to "Ask me for online state (on startup)"
  • Clicking '"addons://" links in the Addons Manager prompted for an application to open it, rather than opening internally
  • The Contacts sidebar "Address Book" drop down was unreadable on Windows
  • vCard attachments were not shown when using "inline" view for attachments
  • Importing an ICS file with TODO items failed
 

silversurfer

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Thunderbird users, who have add-ons installed, may notice that the email client will run checks for add-on updates automatically after updates now once Thunderbird 91.3.1 is installed on the device.

Extensions that are installed in Thunderbird are configured to check for updates automatically by default. Thunderbird users can disable this in the preferences.

The new update check after the installation of updates is designed to reduce the impact of Thunderbird updates on installed extensions. Sometimes, Thunderbird may introduce changes that may interfere with the running of extensions, unless these are updated.
 

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Thunderbird Version 91.3.2 first offered to channel users on November 19, 2021
CHANGED:
  • Date selection in Calendar print settings widget changed to use mini calendar widget
FIXED:
  • "Repair Text Encoding" menu item did not work
  • Troubleshoot Mode menu item did not always indicate whether troubleshooting mode was enabled
  • Message content could be unintentionally hidden due to CSS class names conflicting
  • SMTP server port was reset to "0" after clicking the "Re-Test" button in the Account Setup wizard
  • No "Paste" option was available in the config editor (about:config) context menu
  • Saving a PDF attachment opened in a separate tab saved the email message instead
  • Opening a PDF attachment from a message in a standalone or compose window did move the focus to opened attachment
  • After restart, Thunderbird was not able to restore opened message tabs when the message was in a folder with non-ASCII characters in its name
  • The "pill" indicator was incorrectly shown when sending a message to newsgroup
  • When printing from Calendar, after leaving the "Calendar" settings, there was no way to go back
  • Month pickers in the Calendar print UI lacked scrollbars when the content overflowed
  • Account Manager and Addons Manager were unreadable when using the Dark theme
 

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Thunderbird Version 91.4.0, first offered to channel users on December 7, 2021

Fixes​

  • IMAP startup performance improved for accounts with a multitude of folders
  • Thunderbird failed to send messages when configured to use an IPv6 SMTP server by IP address (instead of a hostname)
  • Forwarding messages with attachments sometimes failed
  • Printing multiple messages at once was not possible
  • Non-utf8 news groups were not supported
  • Thunderbird stalled after sending a message with NNTP and SMTP recipients
  • Using Thunderbird with multiple language packs caused high RAM and CPU use and sluggish performance
  • Clicking a "mailto:" started the composer with the default sending identity instead of a configured alternate
  • Drag and dropped text into a plain text message in the compose window was handled inconsistently
  • FileLink messages did not display correctly when viewed in Outlook
  • In account setup, after selecting an extension provided protocol, it was not possible to create an IMAP/POP account
  • Multiday selections were not cleared when changing week viewed
  • When creating a new event by clicking and dragging the mouse to create a box, the view did not auto-scroll after reaching the bottom
  • Calendar Invitation Panel did not scroll when multiple invitations were pending
  • Calendar print dialog did not have a cancel button
  • Various security fixes
 

silversurfer

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Thunderbird 91.4.0 improves the performance of the email client in several scenarios. Installations with "a multitude of folders" will see improved startup performance after the installation of the new version.
Thunderbird installations with multiple language packs will also see improvements, as the engineers fixed an issue that caused high RAM and CPU usage resulting in a "sluggish performance".
 

silversurfer

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How to configure Thunderbird to open emails in windows​

Here is how you configure Thunderbird to open emails in separate message windows or a single window.
  1. Open the Thunderbird email client, if you have not already.
  2. Select Tools > Preferences. Thunderbird may not display the menubar at the top by default. You can display it temporarily with a tap on the Alt-Key on the keyboard.
  3. While the General tab is active, scroll down to the Reading & Display section.
There you find the preference "open messages in". It has four options, of which three determine how Thunderbird opens messages that you select:
  • A new tab -- This is the default option; emails are loaded in tabs, with each email being loaded in its own tab. Tabs get reloaded when Thunderbird is started the next time, provided that it has not been closed before.
  • A new message window -- Opens messages in their own window. Multiple windows are created, one for each email that you open this way.
  • An existing message window -- Opens a maximum of one window for all emails. When you select a new email, the old is unloaded and the new message is displayed.
The fourth option determines how move or delete operations interfere with open emails. You can check the option -- close message window/tab on move or delete" to close tabs or message windows automatically if the loaded email is moved or deleted.

The changes that you make take effect immediately. Just select another option if you want to switch again or restore the default behavior of Thunderbird.
 

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