This is a maintenance release which fixes a couple of issues with the new Ubuntu 20.04 release. For a detailed list of changes see Changelog.md.
Nominatim 3.5.x installations can be updated directly without changes to the database. Make sure to run ./utils/setup.php --create-functions --enable-diff-updates after setting up the new release to apply all changes to the SQL code. For upgrading from older versions please consult the migration guide.