The latest version of kiwitrees (3.3.10) is now available. It can be downloaded from the downloads page at kiwitrees.net. This version brings compatibility with PHP version 8 (up to version 8.0.14), and MySQL version 8; plus a new Census Assistant for the England & Wales 1921 Census.
The upgrade process is very straightforward, but due to the new versions of PHP and MySQL you should check the upgrade page before proceeding.
As always, a list of all the changes is available on the changes list page.