Thunderbird Desktop
Version 140.4.0esr | Released October 14, 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.
For help and a quick start on Thunderbird 140, see Thunderbird 140 Eclipse FAQ
For more on all the new features in Thunderbird 140, see What’s New in Thunderbird 140.
System Requirements: Details
- Windows: Windows 10 or later
- Mac: macOS 10.15 or later
- Linux: GTK+ 3.14 or higher
What’s Changed
changed
Account Hub is now disabled by default for second email account
changed
Flatpak runtime has been updated to Freedesktop SDK 24.08
What’s Fixed
fixed
Users could not read mail signed with OpenPGP v6 and PQC keys
fixed
Image preview in Insert Image dialog failed with CSP error for web resources
fixed
Emptying trash on exit did not work with some providers
fixed
Thunderbird could crash when applying filters
fixed
Users were unable to override expired mail server certificate
fixed
Opening Website header link in RSS feed incorrectly re-encoded URL parameters
