New features

• TLS 1.3 support
• Added the "Tools | WebDAV Server" menu command
• Server certificates presented by TLS/HTTPS servers are cached to disk together with the endpoints on which they were seen
• Added a new TLS tab to S/MIME and TLS Preferences, with options for the cache folder, retention period, cache size, and clearing the cache
• Added "View certificate..." to certificate lines in the account log, showing the full certificate chain sent by the server

Fixes

• Reverse DNS was used even when the /SMTPHOST= parameter was specified
• Fixed a crash in the message dispatcher when a screen reader requested the name of a list
• Fixed an endless Microsoft login loop after an IMAP account was denied an OAuth token
• Fixed the classic message pane looping and leaking memory when a calendar invitation (METHOD=CANCEL) was cancelled
• Fixed the thread view rewriting the calendar every time a message was re-rendered
• Fixed Accept/Decline causing a fault on an invitation whose event had been deleted from the calendar
• Fixed Type 3 (subset) glyphs being skipped by the PDF-to-HTML converter
• File open dialogs no longer refuse read-only files or files on write-protected media