They did the thing that Tavis complained about:
"No need to trust us, your data stays on your device (safely encrypted)"
You still need to trust that the software is secure.
You still need to trust that the software is secure.
I would definitely use the browser password manager, if I could choose where to sync the data to. I think it's possible with firefox, but it's not straight forward.
I personally trust pfp, because the creator is doing audits of browser addons and publishes them on his blog. They are very well explained.
Also the code is quite compact compared to the other password managers. LastPass, 1Password and Bitwarden have more than 100,000 lines of code, including many third party dependencies. So an audit of PfP is more feasible.