Function zebra_chain::sapling::keys::find_group_hash

pub(super) fn find_group_hash(d: [u8; 8], m: &[u8]) -> ExtendedPoint

FindGroupHash for JubJub, from zcash_primitives

d is an 8-byte domain separator (“personalization”), m is the hash input.

https://zips.z.cash/protocol/protocol.pdf#concretegrouphashjubjub