I have a problem with retrieving the current page document width from Mozilla Firefox. While the rest of the browsers report the correct width of the document, Firefox reports a smaller one (example: at screen resolution of 1920x1080 IE, Chrome and Safari reports 1920 while Firefox reports 1903). I use document width in $(document).ready(function() { ... }); to reposition a div element. Funny this is that after using alert() inside this function, the element reposition correctly, though the document size is still smaller than other browsers.