New features

• Autocrypt Level 1 — opportunistic e-mail encryption with automatic peer-key tracking and send-time recommendations
• Markdown attachments: .md/.markdown files are tagged text/markdown and rendered as Markdown in ThreadView
• "Copy Image" command added to ThreadView and HTML message-viewer popups
• Key Manager can now add subkeys to an existing OpenPGP key
• Generate ECDSA/ECDH (NIST P-256) subkeys for existing OpenPGP keys
• Generate OpenPGP key and subkey revocation certificates
• Smart account select
• IMAP NOTIFY (RFC 5465): one monitoring connection now watches all mailboxes for changes
• IMAP UID MOVE (RFC 6851): server-atomic message moves with no transient duplicate
• OpenPGP keys now live in a transactional SQLite keyring (keyring.db) with on-demand lookups
• Text attachments are scanned for inline OpenPGP blocks, so Import Key / Decrypt / Verify are one click away
• Encryption now always includes the sending identity's key, so the Sent copy stays readable
• PDF Signatures support - verify, sign-and-reply, sign-and-save
• Encrypt and Sign now work in Conversation Thread View in the Quick Reply; toggles are seeded from account defaults
• Key-picker dialog is now displayed if several secret keys can decrypt the same message
• It is now possible to decrypt messages sent with hidden recipients (gpg --throw-keyids wildcard key IDs)
• "Copy Public Key" copies the selected key's armored public key to the clipboard in the PGP Key Manager
• Key Manager opens modeless — it no longer blocks the rest of the program or app exit

Improvements

• Copy/filter destination folder now updates incrementally instead of a full re-read
• Higher-contrast text selection color in pure-HTML view under the dark theme
• Auto-decrypt on thread load restored in the Conversation Thread View, silent-only — uses already-unlocked keys, never prompts
• Replying to an encrypted message now defaults the editor to Encrypt

Fixes

• Fixed iCloud calendar events all collapsing onto a single date/time (CalDAV multiget hrefs)
• Fixed iCloud CalDAV sync failing with 400 Bad Request on pathless server URLs
• Fixed CEF (HTML) views being disabled when The Bat! runs elevated ("As administrator")
• Zoom now works in the plain-text editor and in the CEF thread view
• Fixed an exception when replying from the Mail Ticker message list window
• Fixed calendar reply using a wrongly quoted recipient address
• Checked menu items were invisible in the Windows 11 light theme
• Fixed font color for color groups in the folder list
• Editor Toolbar buttons were invisible in a dark theme
• Accessibility: restored screen-reader (NVDA) support on Win64 (WM_GETOBJECT gate)
• Accessibility: date-group separator rows are now announced to screen readers
• Fixed garbled IMAP Subject/From/To/CC/BCC when servers return raw UTF-8 ENVELOPE (RFC 9051/6855/6532)
• Fixed non-ASCII text attachments appearing as mojibake in the thread-view preview (now decoded to UTF-8)
• Fixed long-dash auto-replace in the HTML editor
• Sent copy is always encrypted to the sender's own identity key, also when signing with the default key
• Decryption tries every matching own key instead of giving up after the first refused passphrase
• Encrypt dialog now states the real per-address reason a recipient cannot be encrypted to
• Replies to encrypted messages quote the decrypted text instead of the armored ciphertext
• Fixed passphrase dialog dropping the typed passphrase and selecting the wrong key on cancel
• Fixed mojibake in decrypted inline-PGP messages (UTF-8 rendered in system codepage) in Conversation Thread View
• Encryption/signature icons (rebuilt bundle with Material Icons font) in the Conversation View are restored
• Fixed date-time separator being trimmed when restoring from backup
• Fixed exception after previewing an ICS file, deleting the mail and moving to another folder
• Fixed OAuth authentication for Outlook.com and Microsoft 365