Sadly, it's time to close up the TT for the year. I'm planning to leave it parked beside of the garage, which will help shield it from the winter winds. When not used in the summer, I keep it plugged in with the refrigerator running. For winter, I'm thinking of unplugging the unit, pulling the battery. Does anyone keep their's plugged in over the winter?
If you have a smart converter then it's your choice - I keep my RV plugged in largely because it keeps my chassis battery charged up and if ice storm and loose power I can retreat to rig without having to lug batteries etc.
During the season I keep our trailer here at the house, plugged in 24/7 but ONLY because the trailer itself is protected from a variety of incoming source power errors by a Progressive EMS ... if it weren't no way I'd leave it plugged in, as the OP seems to be planning to do over the winter. For winter storage I strip the trailer and bring the battery into my workshop where I can periodically put it on a stand alone charger.
When not in use and stored in our side yard our rig is plugged in 24/7. During active RVing season fridge is on and stocked, with batteries always fully charged we can simply hitch up and go in a moments notice.
We keep MH plugged in , batteries in place, refer on with some type of product inside(water) and small heater on. Leaving refer on helps to prevent the cooling unit from rusting out. Placing products in refer helps to make it work. In the event of power outages in house, we have a place ready for occupancy.
Most people with the capability do stay plugged in all winter. Keeping the batteries charged will prevent freezing damage and will allow you to run stuff (furnace etc) over the winter to keep things limbered up. I think you should shut the fridge off though, open it up and let it air out.
If you unplug, pull the batteries and put them on a shelf in the garage. If you want you can put a battery minder on it, or just charge it up in the spring.