To reproduce this bug, you can simply try: <body></body> <script> document.body.contentEditable = true; document.body.innerHTML = "<p>Test1</p><p style='min-height:14.0px;'><i></i></p><p>Test2</p>" document.execCommand("SelectAll"); document.execCommand("InsertUnorderedList"); </script> I think it maybe caused by the function "InsertListCommand::listifyParagraph" in InsertListCommand.cpp, the VisiblePosition judgement may have failed because there's a i tag contained in the paragraph, but I am not so sure.