<p>JS timers should be paused while a modal dialog (or alert) is displayed.</p> <p>Please disable popup blocker for this test.</p> <div>0</div> <script> function f() { var d = document.getElementsByTagName("div")[0]; d.innerHTML = parseInt(d.innerHTML) + 1; } var timerId = setInterval(f, 100); alert("Numbers in main window should not increase while this alert is displayed"); showModalDialog("data:text/html,<p>Numbers in main window should not increase while this modal dialog is displayed</p>"); document.getElementsByTagName("div")[0].innerHTML = "DONE"; clearInterval(timerId); </script>