Auto-fill credentials from Bitwarden during sign in

I am using https://github.com/bitwarden/android 2024.11.3 on Android 13, have set it up as "Android settings > passwords and accounts > auto-fill service > Bitwarden", and would like to be able to "Raindrop > sign in > long-press password > three dots > auto-fill", but Android tells me "Contents can't be auto-filled" in a small popup bubble at the bottom of the screen.