Thunderbird Desktop
Version 158.0 | Released October 13, 2026
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
What’s Changed
changed
Quick filter responsiveness has been improved
changed
ExtensionSettings policy installs add-ons from update_url when install_url not set
What’s Fixed
fixed
Copy Link Location only copied detached attachment filenames instead of full paths
fixed
Thunderbird could crash while performing a Body search
fixed
Attach File dialog failed to open when the previously used folder was unavailable
fixed
Troubleshooting falsely reported crash reports were not configured when available
fixed
Right-clicking inline images zoomed them instead of opening the context menu
fixed
Switching to Unified Folders could leave All Folders enabled and not change view
fixed
Archived Inbox folders ignored localized names and appeared as "INBOX"
fixed
OpenPGP key management had unlocking, handle leak, and protection state issues
fixed
OpenPGP backup password text could not be copied and context menu was transparent
fixed
Quick Filter failed to match accented names when searching without accents
fixed
Holding Ctrl+Enter could unintentionally confirm the send prompt and send duplicates
fixed
Plain-text inline forwards omitted signatures placed below the quote
fixed
Remote content exceptions without a scheme only applied to HTTP, not HTTPS
fixed
Remote content exceptions incorrectly allowed wildcard hostnames like *.example.com
fixed
Saved CalDAV/CardDAV credentials could be forgotten after restarting Thunderbird
fixed
CardDAV setup failed without prompting for a password
fixed
CardDAV address book sync failed to fetch newly added contacts
fixed
CardDAV updates could corrupt vCard REV timestamps
fixed
CardDAV discovery could fail on valid multi-status responses with mixed status codes
fixed
SMTP Kerberos authentication failed on Linux with STARTTLS
fixed
POP accounts repeatedly showed connection errors when Thunderbird started offline
fixed
Matrix SSO with Save Token disabled reopened the login flow indefinitely
fixed
RSS filtering could lose tags and stall processing of later feed items
fixed
CalDAV password prompts did not identify the username or calendar
fixed
Calendar event edits could fail with localization error in the event dialog
fixed
Updated calendar credentials were not saved from the authentication prompt
fixed
Visual and UX improvements
