There are definitely different models/shapes of towel holders. But as I said, we are not sure about that yet anyway. So a door that is as wide as the shower tray (i.e. 90-100cm) probably won’t happen. More likely a sliding door half as wide or a sliding door on each side, so you can basically enter and exit at the corner. There are many possibilities. And if the door to the toilet opens, the towel holder between the shower and the bathtub is also too far away. There, a solution where you exit at the corner is better.