There have been many big features added to PostgreSQL 13, like Parallel Vacuum, de-duplication of indexes, etc., and a complete list can be found at PostgreSQL 13 release notes. Along with the big features, there are also small ones added, including dropdb force. Dropdb force A new command-line option is added to dropdb command, and [&]

https://www.percona.com/blog/2020/10/01/postgresql-13-new-feature-dropdb-force/