Mail: Added ParsingHeader event to MailMessage and MimeEntity, making it possible to custom-process headers on input.
SSH: Added new properties to SshCipher to make it possible to determine IDs of active ciphers.
SSH: Added workaround for a weakness in legacy CBC ciphers.
TLS Core: Enhanced TlsSocket.Timeout property to apply to subsequent Send, SendAsync, Receive and ReceiveAsync methods even when TLS is already active.
TLS Core: Improved and unified behavior of the TlsSocket Shutdown/ShutdownAsync methods when negotiation has not been started.
TLS Core: Improved TLS exception reporting.
TLS Core: Logging improvements.
TLS Core: Optimizations in TLS 1.3 internals.
TLS Core: Support for the TLS 1.3 record with empty application data payload and random padding.
TLS Core: Unified TlsSocket.Cipher property behavior across TLS versions.