I\' trying to use window.pageYOffset & window.scrollMaxY to calculate the current page progress. This approach works under FF3.5 but under webkit w
Alternative to window.scrollMaxY:
window.scrollMaxY
document.documentElement.scrollHeight - document.documentElement.clientHeight
gives same result as window.scrollMaxY with ie7, ie8, ff3.5, Safari 4, Opera 10, Google Chrome 3 under DOCTYPE XHTML 1.0 Transitional.