What happens to items left in Mordenkainen’s Magnificent Mansion?


Recently, the question arose as to what happens when you leave objects you own in Mordenkainen’s Magnificent Mansion. The spell description does not specify if you always conjure the same Mansion, or if it is a different one. So what happens if I leave something like my magic short sword in it? Or even a mundane item, like my mundane pottery?

The spell says that creatures are expelled when the spell ends, and it says what happens to things from the mansion that you want to take outside, but there is nothing about items taken into the mansion. Is there any information in the rules, somewhere?