I am looking for a Zigbee door/window contact, that comes as an alternative for an Homematic HM-Sec-Sco. The benefit of the HM-Sec-Sco is that is uses a photocell / light barrier to detect the window’s state. This fits the typical German/European better, as you mount the sensor next to the window and stick a little piece of reflecting tape at the side of the window sash.
All of the Zigbee sensors I found are using magnets and to work, the window must be embedded flat into the frame.