Most of the gridlines are connected, but the ones closest to the top are part of the antenna system. They are not connected to the circuits for heating the glass.
It's possible that some of your gridlines are broken, but if it's just at the top area of the rear window it could just be the antenna grid you are looking at. There is a slight visible difference between the lines on the regular grid and the antenna grid.
It's possible that some of your gridlines are broken, but if it's just at the top area of the rear window it could just be the antenna grid you are looking at. There is a slight visible difference between the lines on the regular grid and the antenna grid.
