It could be anything.
This is an intriguing mystery. Porsche is currently testing a 718 Cayman with widened front fenders. But the real mystery is what the company is doing here. Although the fender extensions may be placeholder pieces, their purpose is not entirely clear. Because the track on this vehicle isn’t much wider, it doesn’t seem like larger components are necessary. A unique detail is the use of decals on the body. They’re not identical. Some are just one dot with a semicircle surrounding it, while others have multiple dots. This could be used for tracking purposes. These images could function as QR codes and engineers can track their movements from the side.
This could also be used to capture performance data. Porsche could be able monitor the decals’ location and digitally replace the 718 Cayman with another vehicle. It is also possible that Porsche may be working on the next generation 718 Cayman. It is unlikely that we will see it in the next few years. It was launched in 2016 so engineers may have already begun work on a successor.
Recent rumors suggested that the Boxster and Cayman could become EVs. An concept is being considered. This vehicle does not have the decals we normally see on electrified vehicles that are being tested in Germany. The company could be working on both an electric and a combustion engine for the next generation.
It is possible that the vehicle may not be related to either the Cayman and Boxster. Porsche could be trying to trick us by using the body so they can create a new vehicle.