ShadowRoot object is not recognized by instanceof operator. Chrome 25.0.1364.0 canary. Test: <html> <head> <script type="text/javascript"> function test() { if (document instanceof ShadowRoot) { alert('This is the End!'); } else { alert('Ok'); } } </script> </head> <body onload="test()"> </body> </html> Observe the console: Uncaught ReferenceError: ShadowRoot is not defined
Nice catch. https://bugs.webkit.org/show_bug.cgi?id=105385 will fix this. Note that we have to use WebKitShadowRoot instead of SahdowRoot. e.g. someElement instanceof WebKitShadowRoot. *** This bug has been marked as a duplicate of bug 105385 ***