Nobody Nose Libby Like Sabrina Nose Libby - S3-E9
Other mistake: After Salem and Sabrina are shrunk down into the toy plane you see the kitchen from inside the cockpit, but when they are shrunk down to be tiny enough to go into Libby's nose, the view from inside the cockpit is the same as it was before they were shrunk down even further. Since they are that much smaller everything should be seen as much bigger.