Hi experts. We bought a home where the inside of the microwave door panel had been somehow "burned" through? I don't know if they put something metal in the microwave, but it melted the first, clear inner panel, and zapped the mesh grating between the two plastic panels. My question is this... do I have to replace the whole door, or is there a way to just replace the "window" portion of the microwave? How would I go about doing either one? Thanks!