Warm and fully topped off batteries are key. I had a P3P-down (auto-land) when there was that firmware issue in the end of 2015. Partly my fault as it was about 45 F and I started with 73% battery charge. I have since flown in 0 degrees with a P3P and P4’s without too many problems aside from battery cold warning. Make sure you let the drone hover for a good minute to get the battery juices going.
Different question Re CONDENSATION - my DSLR training was to always bring a plastic bag outside in the cold when shooting and then before heading inside, place the camera and lens in the bag and tie it off, then bring that inside to warm up. The theory being, like eyeglasses, the camera and electronics will hit the warm and more humid air and fog (condense) up. However, if in a bag, the condensation will collect on the bag and not on the camera. Once at room temperature, then it’s safe to get it out of the bag. I “try” to do this with my drone or at least put it back in the cold travel box before coming inside. Has anyone else done this?