Beta Notes

Thunderbird Desktop

Version 74.0beta | Released February 17, 2020

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.

These notes apply to Thunderbird version 74 beta 2 released February 28, 2020.

Thunderbird 74 integrates Lightning, Thunderbird's calendar add-on, into Thunderbird.

If you have installed Lightning, it will be automatically removed. Refer to this Calendar troubleshooting article in case of problems.

Thunderbird 74 no longer supports "legacy" extensions.

What’s New

new

MailExtensions: API to block sending a message from compose window

1532528

new

MailExtensions: API to interact with message in compose window

1590121

What’s Changed

changed

Add-on support: As of version 74.0 beta, Thunderbird only supports MailExtensions and MailExtension Experiments. Restartless add-ons and non-restartless legacy add-ons using XUL overlays are no longer supported.

1614237

changed

Calendar: The Lightning calendar add-on is now integrated into Thunderbird

1608610

changed

Account Manager moved to a tab

1610445

changed

Improved UI of global search results tab

1022228

changed

MailExtensions: Allow commands.update() to disable a command

1475043

changed

MailExtensions: Allow browser.query.messages to query by tag

1600547

changed

MailExtensions: Changed folder enumeration to return tree structure rather than list

1606584

changed

MailExtensions: Exposed message "Junk" status to addons

1610457

What’s Fixed

fixed

When copying messages from an IMAP folder to a local folder, offline store wasn't used

505456

fixed

SMTP timeout when forwarding message via filter

1222046

fixed

Partial updates not working

1410512

fixed

Thread collapsed when opening news message in a new window

1526765

fixed

Addons not automatically updated to compatible version after upgrade from Thunderbird 60

1574183

fixed

Opening the properties of a folder sometimes hung on Mac

1574322

fixed

Multiple master password prompts. Fixed by prompting for master password at startup time.

1610390

fixed

Offline replication of LDAP databases sometimes failed to replace an earlier copy

1608304

fixed

Calendar: Last day of multiple-day event not displayed

1572964

fixed

Chat: Avatars not displayed in tooltips

1592422

Changed and Fixed in Beta 2

What’s Changed

changed

Thunderbird will now display a popup window when starting up on a new profile

1590036

changed

MailExtensions: Action APIs now provide tab and click information

1617514

changed

MailExtensions: Allow composeAction to open popups from onBeforeSend

1617742

What’s Fixed

fixed

Long subject lines did not wrap in message header

1616764

fixed

Account Manager in tab not consistent with Options/Preferences in tab

1613758

fixed

"Get New Messages for All Accounts" not working for OAuth2-authenticated IMAP accounts

1593611

fixed

Searching in message bodies led to false negatives under some circumstances in quoted-printable encoded HTML bodies

1614796

fixed

Calendar: Starting with 74.0 beta 2, building Thunderbird with --enable-calendar is deprecated, and should be removed from your mozconfig file

1612190

fixed

Chat: macOS users were not be able to connect to a server

1615714

Known Issues

unresolved

WebExtension toolbar button badges not displayed

1599275

unresolved

Address auto-completion not working on Mac if the Mac address book is enabled (File > Use Mac OS X Address Book)

1615468

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