Kitty took flight yesterday night: We left the apartment door open for a few minutes not to let the cat out, but to let some air in, and she used the chance to slip out. A search of all fifteen floors (for once I was thankful for them being illuminated so well all through the night) turned up nothing and we were worried if she could find back (cats are supposed to be good at that, but all doors basically look the same here) or if a potential finder would know where to return her (Kitty does not wear a necklace or tags of any kind). Fortunately Cissy discovered her on her way to work in the morning, hiding behind a nearby air conditioner.