Function polkadot_node_primitives::approval::v1::babe_unsafe_vrf_info

pub fn babe_unsafe_vrf_info(header: &Header) -> Option<UnsafeVRFPreOutput>

Extract the slot number and relay VRF from a header.

This fails if either there is no BABE PreRuntime digest or the digest has type SecondaryPlain, which Substrate nodes do not produce or accept anymore.