Vertical and horizontal here seem quite confusing. The absorptive polarizer with vertical lines drawn on it passes through photons passing through PBS, which game calls horizontal. So either the polarizer lines have negative logic (indicating what is absorbed, not passed through), or there is some inconsistency. Similarly, the horizontal polarization is represented as photon bouncing up and down ("vertically") if it travels right. This can get confusing.

I wonder if some polarization arrow can be drawn somehow, like: https://encrypted-tbn0.gstatic.com/images?q=tbn:ANd9GcTAlDUU...