They didn't 'switch' over. The KDBX 4 format introduces Argon2 as a possible KDF, in addition to AES-KDF which has been the dominant KDF in KeePass and its impl

They didn't 'switch' over. The KDBX 4 format introduces Argon2 as a possible KDF, in addition to AES-KDF which has been the dominant KDF in KeePass and its implementations. Even the project with most contributors - KeePassXC, doesn't yet support KDBX 4, and work on it doesn't look like its moving either[1]. Most other implementations also don't support KDBX 4 format. [1]: https://news.ycombinator.com/item?id=14634253 https://news.ycombinator.com/item?id=14634253