Right now on Firefox for Android (I use it on macOS, Windows, Linux, and iOS without issue) I’m only able to sign into websites requiring passkeys with my on-device or Google account passkeys. I can’t sign in using my 1Password passkeys like I do on all the other platforms. There was a bug fix I was watching the status of (got fixed a few weeks or a month ago) that should be included in the next Firefox release (128), fixing this annoying issue :-)

As far as what passkeys are, it’s basically password-less logins: https://passkeys.io and https://passkeys.dev

1 more release and 3rd party passkeys will work on Android (⁠ﾉﾟ⁠0ﾟ⁠)⁠ﾉ⁠~