BitWarden works fine. I'm using Linux/Firefox as well, the rest of the time is on Windows/Chrome. It's 100% open source: https://bitwarden.com/
No cloud, only USB keys. The thing is, I lost two of these USB keys! Had to rotate my passwords ;)
[1]: https://github.com/dyne/Tomb [2]: https://github.com/zx2c4/password-store [3]: https://github.com/roddhjav/pass-tomb
https://github.com/mprasil/bitwarden_rs
This is a 3rd party implementation of the bitwarden api, which gives me more confidence in the 1st party product.