fingerprint authentication doesn't always work when coming out of suspend mode

If you follow https://wiki.debian.org/SecurityManagement/fingerprint%20authentication you get fingerprint authentication on the lock screen.

However, sometimes fingerprint authentication is not available when coming out of suspend mode and you can only type in a password.

I'm not sure why. This could be an issue with fprintd or the fingerprint reader not waking up by the time the lock screen comes up. Either way, I think the lock screen should keep checking for fprintd to be ready instead of having to unlock and relock again for the fingerprint reader to work again.