Why do I not need to short the existing chime when installing a Ring 4?

In an existing doorbell system with a mechanical chime, the doorbell is a switch that just closes the circuit to the chime. Instructions for older Rings say that I need to short the connections in the chime in order for the doorbell wires to get power. In this case, the doorbell/Ring is no longer a switch. That all makes sense.However, the instructions for the Ring 4 make no mention of rewiring the chime. Without that rewiring, the Ring 4 won't get any power because the circuit is always open.What am I missing?https://support.ring.com/hc/en-us/articles/360059528911-How-to-Physically-Install-Your-Ring-Video-Doorbell-4-With-an-Existing-Doorbell