Extracts master key material from an EIP-191 signature over the master key message. The raw 65 signature bytes ARE the master key material.
0x-prefixed hex string (65 bytes = 130 hex chars + 0x).
65-byte Uint8Array containing the raw signature bytes.
Extracts master key material from an EIP-191 signature over the master key message. The raw 65 signature bytes ARE the master key material.