If you look into an electron mirror, you don’t expect to see your reflection. As [Anthony Francis-Jones] points out, what you do see is hard to explain. The key to an electron mirror is that the electric and magnetic fields are 90 degrees apart, and the electrons are 90 degrees from both.
This is a companion discussion topic for the original entry at https://hackaday.com/2024/02/23/mirror-mirror-electron-mirror/