==================
- Add support for Python 3.9.
- Move from Travis CI to Github Actions.
- Supply manylinux wheels for aarch64 (ARM).
- Fix the pure-Python implementation to activate a ghost object
when setting its ``__class__`` and ``__dict__``. This matches the
behaviour of the C implementation. See `issue 155
<https://github.com/zopefoundation/persistent/issues/155>`_.
- Fix the CFFI cache implementation (used on CPython when
``PURE_PYTHON=1``) to not print unraisable ``AttributeErrors`` from
``_WeakValueDictionary`` during garbage collection. See `issue 150
<https://github.com/zopefoundation/persistent/issues/150>`_.
- Make the pure-Python implementation of the cache run a garbage
collection (``gc.collect()``) on ``full_sweep``, ``incrgc`` and
``minimize`` *if* it detects that an object that was weakly
referenced has been ejected. This solves issues on PyPy with ZODB raising
``ConnectionStateError`` when there are persistent
``zope.interface`` utilities/adapters registered. This partly
reverts a change from release 4.2.3.