Thunderbird Desktop
Version 136.0beta | Released February 6, 2025
Check out the notes below for this version of Thunderbird. As always, you’re encouraged to tell us what you think, ask for help, or file a bug in Bugzilla.
These notes apply to Thunderbird version 136 beta 3 released February 24, 2025.
System Requirements: Details
- Windows: Windows 10 or later
- Mac: macOS 10.15 or later
- Linux: GTK+ 3.14 or higher
What’s New
new
Messages are automatically adapted to dark mode with a quick toggle in the header.
new
New "Appearance" Settings UI to globally control message threading/sorting order.
What’s Changed
changed
Criteria for closing idle message databases.
What’s Fixed
fixed
Thunderbird Release channel was not displayed in "About Thunderbird".
fixed
Crash could occur when shutting down during MAPI send.
fixed
The error message for compacting a corrupted local folder was not useful.
fixed
Deleting or detaching attachments in a saved .eml file appeared to work but failed.
fixed
Some messages may have been threaded incorrectly in unified folders.
fixed
Unified folders could become unusable instead of being automatically rebuilt.
fixed
Folders at level 3+ were not auto-discovered when IMAP subscriptions were ignored.
fixed
New subfolder did not inherit parent view, sort order, sort type, or columns.
fixed
With "Fetch headers only" enabled, messages could not be sorted by size.
fixed
Selecting starred messages did not update immediately.
fixed
Marking a unified folder as favorite did not show it in favorite folders.
fixed
The UI could falsely report a message as encrypted when a null cipher was used.
fixed
Search messages dialog list could not be sorted by clicking the header icon.
fixed
Sending to multiple SMTPs could fail silently due to missing address book.
fixed
Changing the UI font size did not apply to some dialogs.
fixed
Deleted Gmail messages stayed visible until compact/expunge, despite settings.
fixed
Add-ons: Context menu entries were incorrectly aligned.
fixed
Some functionality was missing for newsgroup messages opened from a file or URI.
fixed
Visual and UX improvements
Fixed in beta 2
What’s Fixed
fixed
Middle-click autoscroll cursor appeared without arrows instead of expected design.
fixed
Release channel incorrectly showed What's New page after update.
fixed
Notifications for new mail were not showing for IMAP.
fixed
Message and folder lists could display incorrect line spacing after restart.
Fixed in beta 3
What’s Fixed
fixed
Users with many folders experienced poor performance when resizing message panes.
fixed
"Replace" button in compose window was overwritten when the window was narrow.
fixed
Export to mobile did not work when "Use default server" was selected.
fixed
"Save Link As" was not working in feed web content.
fixed
Sort indicators were missing on the calendar events list.
