The major focus of this release is the documentation, now automatically generated and available at https://btclib.readthedocs.io/en/latest/. Hopefully this will help introducing new users and devs to the library and existing users/devs to deal with the any refactoring.
A relevant "lost leading zeros in entropy" bug has been fixed. See the issue and the provided links for more details: fametrano#15.
The major new feature is Bitcoin message signing with compact encoding.