This tests the blur() on on shadow host should work when a shadow host contains a focused element in its shadow DOM subtrees property (bug 81102) On success, you will see a series of "PASS" messages, followed by "TEST COMPLETE". getNodeInComposedTree('shadowHostA/childInTreeOne').focus() PASS document.activeElement.id is "shadowHostA" getNodeInComposedTree('shadowHostA').blur(); shadowHostA onblur called! PASS document.activeElement is document.body PASS getNodeInComposedTree('shadowHostA/').activeElement is null PASS getNodeInComposedTree('shadowHostA/shadowHostB/').activeElement is null PASS getNodeInComposedTree('shadowHostC/').activeElement is null getNodeInComposedTree('shadowHostA/shadowHostB/childInTreeTwo').focus() PASS document.activeElement.id is "shadowHostA" getNodeInComposedTree('shadowHostA/shadowHostB').blur(); shadowHostB onblur called! shadowHostA onblur called! PASS document.activeElement is document.body PASS getNodeInComposedTree('shadowHostA/').activeElement is null PASS getNodeInComposedTree('shadowHostA/shadowHostB/').activeElement is null PASS getNodeInComposedTree('shadowHostC/').activeElement is null getNodeInComposedTree('shadowHostA/shadowHostB/childInTreeTwo').focus() PASS document.activeElement.id is "shadowHostA" getNodeInComposedTree('shadowHostA').blur(); shadowHostB onblur called! shadowHostA onblur called! PASS document.activeElement is document.body PASS getNodeInComposedTree('shadowHostA/').activeElement is null PASS getNodeInComposedTree('shadowHostA/shadowHostB/').activeElement is null PASS getNodeInComposedTree('shadowHostC/').activeElement is null getNodeInComposedTree('shadowHostC/childInTreeThree').focus() PASS document.activeElement.id is "shadowHostC" getNodeInComposedTree('shadowHostA').blur(); PASS document.activeElement.id is "shadowHostC" PASS getNodeInComposedTree('shadowHostA/').activeElement is null PASS getNodeInComposedTree('shadowHostA/shadowHostB/').activeElement is null PASS getNodeInComposedTree('shadowHostC/').activeElement.id is "childInTreeThree" PASS successfullyParsed is true TEST COMPLETE