If I create an element dynamically using the DOM, the shadow gets clipped initially until the next time the page is rendered, eg. by resizing the window. Sample code: var e = document.createElement("div"); e.setAttribute("style", "-webkit-border-radius: 20px; -webkit-box-shadow: 10px 10px 20px rgba(0, 100, 255, 0.8);"); e.style.position = "absolute"; e.style.border = "solid 3px green"; e.style.top = "100px"; e.style.left = "100px"; e.style.width = "100px"; e.style.height = "100px"; e.style.background = "#fff"; e.id = "foo"; document.documentElement.appendChild(e); I am including a border radius here because it demonstrates how this is probably a redraw region problem. Without the rounded border, the shadow is not shown at all.
Argh, I was testing in beta 3. Works fine in latest nightly.