3.2.5.2.13.2 Sending Caret Blink Information PDU

If the server advertises support for Caret Blink Information in the HandshakeEx PDU (section 2.2.2.2.3) structure (using the TS_RAIL_ORDER_HANDSHAKE_EX_FLAGS_CARET_BLINK_SUPPORTED flag), the client SHOULD send the Caret Blink Information PDU (section 2.2.2.15.2) during the connection establishment phase and when the caret blink rate of the client system is changed.