I have some in mine all the time and sometimes builds up on the fins in the fridge if the kids open it up often. In the fridge it will melt and drain out the drain tube (make sure you have the drain tube poking out the vents outside the unit so the water doesn't drain inside. Just open the vent and pull the tube through the vent).
On the freezer I just let it be and then clean up the water after a trip when it thaws. Long term I can't say, but of course you'd want to clean it up from time to time. I've never had it build up longer than 3 weeks.
2018 Jayco Greyhawk 31FS