So, we heard kitchen cabinet doors clacking early this morning. There's one set that doesn't have doors - the oven door wouldn't open if it did - so I sleepily assumed that one of them was running in and out of there and the cabinet next to it, which does have doors.
Awhile after we got up, it occurred to us that we hadn't seen Copper this morning. Turns out she can totally open the bottom kitchen cabinets, and she was happily chilling out in one. Oh, kittens.