尝试使用beforeunload和嵌入的typeform来阻止关闭/刷新，但它似乎没有显示警告消息。我是不是漏掉了什么?
<html>
<body>
<script>
window.addEventListener("beforeunload", function(event) {
event.returnValue = "";
});
</script>
<div class="relative pt-16 m-auto overflow-hidden" style="height: 700px">
<iframe
id="typeform-full"
width="100%"
height="100%"
frameborder="0"
allow="camera; microphone; autoplay; encrypted-media;"
src="https://form.typeform.com/to/AQlHXdch?typeform-medium=embed-snippet"
></iframe>
<script>
type="text/javascript"
src="https://embed.typeform.com/embed.js"
</script>
</div>
</body>
</html>
也许你正在使用Chrome?
Chrome 51删除了页面指定onbeforeunload字符串的功能。(从Safari 9.1和Firefox 4开始，它也被删除了。)https://www.chromestatus.com/feature/5349061406228480
with overscroll-behaviour