102069 2012-11-13 04:44:35 -0800 [Shadow DOM]: Event with both target and relatedTarget in the same tree is not stopped at Shadow boundary 2012-12-06 02:57:36 -0800 1 1 1 Unclassified WebKit DOM 528+ (Nightly build) Unspecified Unspecified RESOLVED FIXED P2 Normal --- 102681 103230 0 sgrekhov webkit-unassigned hayato morrita shinyak webcomponents-bugzilla oldest_to_newest 765469 0 sgrekhov 2012-11-13 04:44:35 -0800 According the Shadow Dom specification "In cases where both relatedTarget and target are part of the same shadow tree, the conforming UAs must stop events at the shadow boundary to avoid the appearance of spurious mouseover and mouseout events firing from the same node.". But in fact such events are not stopped at the Shadow boundary. Run the following example: <html> <head> <script type="text/javascript"> function test() { var d = document; var SR = window.ShadowRoot || window.WebKitShadowRoot; //Shadow root to play with var s = new SR(d.querySelector('#host')); var div1 = d.createElement('div'); div1.setAttribute('style', 'height:40px; width:100%'); div1.setAttribute('id', 'div1'); s.appendChild(div1); var div2 = d.createElement('div'); div2.setAttribute('style', 'height:40px; width:100%'); div2.setAttribute('id', 'div2'); s.appendChild(div2); s.addEventListener('mouseover', function(event) { if (event.relatedTarget.getAttribute('id') != 'div1') { alert('Wrong relatedTarget'); } }, false); d.body.addEventListener('mouseover', function(event) { alert('Event must be stopped at Shadow boundary!!!!'); }, false); var evt = document.createEvent("MouseEvents"); evt.initMouseEvent("mouseover", true, false, window, 0, 10, 10, 10, 10, false, false, false, false, 0, div1); div2.dispatchEvent(evt); } </script> </head> <body onload="test()"> <div id="host"> </div> </body> </html> Event shouldn't buble up to document.body event listener but it bubles. 767927 1 hayato 2012-11-15 04:01:20 -0800 Thank you for the reporting. Let me take a look tomorrow. 784801 2 hayato 2012-12-06 02:57:36 -0800 http://trac.webkit.org/changeset/136818 fixed this. Closing.