Will cotton clothing melt in the microwave?

It's probably best not to dry any clothing in a microwave oven, but I definitely would not dry anything that is 100% cotton in one. As micros don't really produce heat, which dries things, just energy, which heats them - and agreeably may heat the water in the material, producing steam, in a confined micro - probably not going to dry anything. Watch out for the frequently metal zipper or non microwaveable buttons.