Why does window.innerWidth returns 477px even if the window has a smaller width?

When I resize the browser window to a lower width than 477px, window.innerWidth or window.getSize().x (using mootools) still returns 477px.

Anyone ever had that problem? What'开发者_StackOverflow社区s going on here?

The problem occurs in Firefox and Chrome.

workaround: http://jsfiddle.net/H4snF/1 - window.getCoordinates().width returns fine.

When the code gets called, is the window resized? It might be the case where the call to window.getSize().x gets called before you resize the window. Maybe you should attach the call to an anchor element on your page and only call it after the resize.