A long time ago it was the case that browsers would save passwords locally in plaintext. But these days Firefox will encrypt your passwords and host them for y

A long time ago it was the case that browsers would save passwords locally in plaintext. But these days Firefox will encrypt your passwords and host them for you so that they can sync across devices. If you don't trust them there is even an option to host this password server yourself and configure Firefox to point to that instead. The main downside is that the app (Firefox Lockwise) is no longer supported.