Is there any reason this would not work on a Mac and iterm2? I get the initial encryption effect, but sadly, no decryption :). I tried different fonts and iterm

Is there any reason this would not work on a Mac and iterm2? I get the initial encryption effect, but sadly, no decryption :). I tried different fonts and iterm2 settings to no avail. I guess I could try the ncurses option, but curious to see this not work natively. Edit: as helpful comments below me explained, you either have to press another key to decrypt, or launch it with the `-a` option.