Typing your password over a button

Apple came up with this interface behavior that would seem strange before.

When biometric authentication is available, the password input field is hidden. But if something goes wrong, you can still enter your password. However, you can start typing the password even before pressing the “Use Password...” button — any input will take the window to the next state.

Apparently, the password interface is hidden initially for the sake of beauty, and also not to give people the false impression that the password must be entered.

The only annoying thing is that the two states of the window are of different heights, that is, when you start typing the password, the window gets bigger.