You are standing between two mirrors. Your reflection smiles, so you smile. Your reflection moves its hand, so you move yours. It takes a very long while for you to realise that this is the wrong way round.
Madness string 2616
The Location exotic object is defined through a mishmash of IDL, invocation of JavaScript internal methods post-creation, and overridden JavaScript internal methods. Coupled with its scary security policy, please take extra care while implementing this excrescence.