Thunderbird Desktop
Version 142.0 | Released August 19, 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.
System Requirements: Details
- Windows: Windows 10 or later
- Mac: macOS 10.15 or later
- Linux: GTK+ 3.14 or higher
What’s New
new
Visual signatures can be added to PDF attachments opened in Thunderbird
new
'Copy Message Link' and 'Copy News Link' added to header pane 'More actions'
new
Folder copy enabled within mail server accounts and local folders
new
'Reset Folder Order' option added to folder pane to reset custom folder sorting
What’s Changed
changed
'Copy Message Location' removed from mail context menu
What’s Fixed
fixed
Users with attachments open in tabs saw an error on Thunderbird restart
fixed
Notification sounds did not respect operating system's do-not-disturb mode
fixed
Non-English localized Thunderbird created English special folders on first start
fixed
Users were unable to use Fastmail calendars due to missing OAuth settings
fixed
Sending from unified or local folder failed if no default account was set
fixed
Right-clicking 'List-ID' -> 'Unsubscribe' created double encoded draft subject
fixed
On Linux, the close caption button was inactive when mouse was in screen corner
fixed
Toggling dark message mode did not restore focus and scroll position
fixed
Message list scrolled back when returning to mail tab after opening a message
fixed
Deleting a single message in folder using 'Group by Sort' failed after CTRL+A
fixed
New newsgroups were not added in alphabetical order by default
fixed
After updating to version 142, all newsgroup folders were sorted alphabetically
fixed
With Thunderbird closed, clicking a 'mailto:' link to send signed message failed
fixed
Replying could fail with mailnews.reply_quoting_selection.multi_word set false
fixed
Multiple saves while using 'Options' -> 'Send a Copy' resulted in multiple copies
fixed
Thunderbird did not display contact photos in WebP format from CardDAV servers
fixed
Installations from Microsoft Store did not open when clicking 'mailto:' links
fixed
Clicking the backspace icon in the quick filter field cleared the input field
fixed
Initial launch had long load times and UI lag while messages downloaded
fixed
'Mark' -> 'All Read' affected newsgroup messages that had not been fetched yet
fixed
Thunderbird could not reconnect to newsgroups after connection loss until restarted
fixed
Sending a newsgroup post appeared successful when it had actually failed
fixed
Archived RSS feed messages were sent to the archive folder of default identity
fixed
Opening Website header link in RSS feed incorrectly re-encoded URL parameters
fixed
Visual and UX improvements
