This has been addressed here: http://www.rememberthemilk.com/forums/help/6547/ and here: http://www.rememberthemilk.com/forums/help/2614/

Is there anyway we can re-add the key to our window as of now? I have tried clearing my cache and cookies locally, but I think it is a setting tied to my account. any hack or greasemonkey workaround would be acceptable solution for me.