```\n/// @dev Prefix for all TransceiverMessage payloads\n///      This is 0x99'E''W''H'\n/// @notice Magic string (constant value set by messaging provider) that idenfies the payload as an transceiver-emitted payload.\n///         Note that this is not a security critical field. It's meant to be used by messaging providers to identify which messages are Transceiver-related.\nbytes4 constant WH_TRANSCEIVER_PAYLOAD_PREFIX = 0x9945FF10;\n```\n