silversurfer
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- Aug 17, 2014
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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
NEW
Native support for macOS devices built with Apple Silicon CPUs
NEW
Thunderbird now operates in multi-process (e10s) mode by default
NEW
Latvian language support
NEW
New user interface for adding attachments
NEW
Enable redirect of messages
NEW
Ability to change order of accounts in UI
NEW
Allow showing empty CC/BCC rows in compose window
NEW
Warning popup when sending a reply to a likely non-existant email address such as "noreply@example.com"
NEW
Warning popup when public recipients of a message exceeds threshold
NEW
Add support for "X-Unsent: 1" header, to open a saved email in a compose window for editing
NEW
Add support for non-ASCII characters in recipient addresses
NEW
Context menu to expand mail list pills in the compose window to the list of recipients
NEW
Quick Find is now available in the multi-message (thread summary) view
NEW
Keyboard shortcuts to access To/CC/BCC fields of compose window
NEW
Allow pinning folder views to the Folder Pane
NEW
Language packs and dictionaries added to about:support
NEW
PDF.js viewer now included in Thunderbird
NEW
OpenPGP: "Copy Key Id" option added to Key Manager context menu
NEW
OpenPGP: Added config option to disable encrypting saved drafts
NEW
Encrypt mail to BCC recipients (with warning that it will expose the recipients in the list of keys)
NEW
CardDAV address book support
NEW
CardDAV address books automatically detected based on provided user information
NEW
Access to Outlook Contacts; To enable, set ldap_2.servers.outlook.dirType to 3; This setting may cause startup delays.
NEW
Suggest replacements for discontinued/incompatible add-ons
NEW
Chat: Beta-level support for Matrix servers (set chat.prpls.prpl-matrix.disable to false)
NEW
Calendar: Remote calendar auto-detection now supported
NEW
Calendar: Calendar and category colors now displayed in selection dropdowns
NEW
Calendar: "Edit" item added to event context menu
NEW
Calendar: Support opening of .ics files by double-click
NEW
Calendar: Thunderbird now informs the operating system that it knows how to open webcal: URLs
NEW
Calendar: Filter and sort items to be imported in the Import dialog
NEW
Prompt to choose the identity of an accepted calendar invite when no identity matches the event attendees list
NEW
Support mid: URL scheme for Related Links in calendar event dialogs
NEW
Permissions to access calendar and address book are now requested when a GMail account is set up, so that calendar and address book can be accessed without having to re-authorize (see notes)
NEW
Calendar: Per-calendar and global notification settings (in addition to alerts set in events)
NEW
Tasks: Undo/Redo support for event and task creation and deletion

Thunderbird — Release Notes (91.0)
