I've created a simple DIV with a onclick event that change his class to give him the box-shadow when a user click on it. this is the CSS style: div.boxShadowOff, div.boxShadowOn { width:100px; height:200px; position:absolute; top:100px; left:200px; background: #FF8000; padding: 5px 5px 5px 15px; -webkit-border-radius: 5px; float:left; } div.boxShadowOn { -webkit-box-shadow: 5px 5px 10px #888; } and this is the DIV: <div class="boxShadowOff" onclick="this.className='boxShadowOn'"></div> When I click on the DIV he changes the class but WebKit doesn't render the box-shadow. The box-shadow is rendered only if I resize the browser window. Try to see it.
Bug 12729 basically deals with box-shadow invalidation. Maybe it should be retitled to make it easier for people to find it. *** This bug has been marked as a duplicate of 12729 ***