Some time ago my wife and I developed Nitrokey Authenticator – a desktop app for TOTP authentication using both, Nitrokey Pro2 and LibremKey. The latter, however, requires libnitrokey 3.6. We missed the boat for Bullseye. But I did NMU libnitrokey to Debian Unstable recently. It already has migrated to Testing. So those who use Debian’s rolling Testing release can already just go ahead and use their LibremKey with Nitrokey Authenticator.
I’m assuming, both, Nitrokey Authenticator and libnitrokey 3.6 will eventually end up in development branch of PureOS, since it’s based on Debian, but I don’t know the specifics of how PureOS is syncing Debian’s updates.