P Warp Door

P Warp Doors (or P Doors) are Warp Doors that can only be entered when a P-Switch is active. These warp doors made their first appearance in Super Mario World in the Donut Ghost House.

Super Mario World
In Super Mario World, P Warp Doors appeared in the level Donut Ghost House. They had the same sprite as a Warp Door, but with a light blue palette.

Super Mario Maker
In Super Mario Maker, P-Doors were introduced in the version 1.30 update. They were given new sprites for all styles, in the same blue as the P-Switches with a white or blue "P". Unlike in Super Mario World, they are visible as outlines when not active.