Just don’t put metal in one. My neighbor did that an hour ago and started a fire. My first clue was the rumble of a diesel engine, which in my 55+ community at 8:15 pm can mean only one thing...emergency vehicles. Five in total. Destroyed the microwave. Only casualty was the popcorn. That’s the difference between Arizona and Alaska. When I’m in Arizona and I hear the rumble of a diesel at night it’s emergency vehicles. When I’m in Alaska the rumble of a diesel at night means someone is driving by in their pickup truck.
There once was a fad of microwaving CDs...
I do it all the time. But OUTSIDE... lol
https://www.familyguidecentral.com/can-microwaves-melt-metal-yes-and-how-to/