Previous versions was macOS rebased with upstream.
This version is upstream+macOS PR, so it is latest upstream and the future.
If anyone wants to test it out, there is a .pkg installer for Catalina (and newer versions).
For example, the sysctl is completely new, all tunables are finally available.
It should contain assembler/crypto fix, NFS fix etc. Please report issues
so we can move towards the next release. The xattr/xcode problem is known.
zfs-2.1.99-752_g1abfb1ddd
zfs-kmod-2.1.99-752_g1abfb1ddd