Can’t believe noone mentioned this yet:

Any good password manager encrypts and decrypts your password file client side. The server should not even have the ability to read your passwords.

Even in the case of a leak of all of the server’s data, as long as your password for the manager was good, you’ve got nothing to worry about.

I’d say pick a PW manager where both client and server are open source. Pick a strong passphrase. Enjoy.