where does doorbell get it power when button is not pushed for awhile?

Hi Emily. Not sure my question was understood.  When wiring any doorbell to a chime the chime will have two points to connect. One will get a wire from one of the two AC transformer output wires.  The other connection on the chime gets a wire from the doorbell.

The doorbell also has two connector points. One is connected to the other AC transformer output wire. The other connector point on the doorbell is wired to the chime per above. When the doorbell button is pressed it makes a momentary closed connection (completes the AC circuit) and that actuates the solenoid that dings the chime.   Without the button being pushed there is not a completed AC circuit so how does this configuration charge the doorbell camera? Is there some bleeder type circuit inside the doorbell pro that keeps it charged?