Is it my imagination or does Mozilla/Firefox not allow you to move a window to negative screen coordinates? E.g. moveTo(-4,-4). It seems to just treat all negative numbers as 0.
IE handles this fine, and it is necessary if you want simulate a truly maximized window in JS (that is, one that does not have the 4-pixel left-hand application margins that IE will otherwise only remove when you click the Maximization button).