在看某个网站时，看到一段话想复制一下，结果复制不了。想打开F12看看元素进行复制，也不行，没有反应。最后通过打开开发者工具看看，结果一打开就跳到about:blank。
看到这操作一脸懵逼，小样的，还有这种操作。

于是乎复制网址地址，放到Postman中请求看看它的源码如何写的。

看到如下的代码：

 <!-- 应用插件标签 start --><!--屏蔽F12 审查元素--><script>document.onkeydown = function () {//keycode 123 = F12if (window.event && window.event.keyCode == 123) {//如果这个键不能被标志，这个值为 0。event.keyCode = 0;event.returnValue = false;}//keyCode 13 = Enterif (window.event && window.event.keyCode == 13) {window.event.keyCode = 505;}if (window.event && window.event.keyCode == 8) {alert(str + "\n请使用Del键进行字符的删除操作！");window.event.returnValue = false;}}</script><!--屏蔽开发者工具--><script type='text/javascript'>var h = window.innerHeight, w = window.innerWidth;window.onresize = function () {if (h != window.innerHeight || w != window.innerWidth) {window.close();window.location = "about:blank";}}  </script><!--屏蔽右键菜单--><script>document.oncontextmenu = function (event) {if (window.event) {event = window.event;} try {var the = event.srcElement;if (!((the.tagName == "INPUT" && the.type.toLowerCase() == "text") || the.tagName == "TEXTAREA")) {return false;}return true;} catch (e) {return false;}}</script><!--屏蔽复制--><script>document.oncopy = function (event) {if (window.event) {event = window.event;} try {var the = event.srcElement;if (!((the.tagName == "INPUT" && the.type.toLowerCase() == "text") || the.tagName == "TEXTAREA")) {return false;}return true;} catch (e) {return false;}}</script><!--屏蔽剪切--><script>document.oncut = function (event) {if (window.event) {event = window.event;} try {var the = event.srcElement;if (!((the.tagName == "INPUT" && the.type.toLowerCase() == "text") || the.tagName == "TEXTAREA")) {return false;}return true;} catch (e) {return false;}}</script><!--屏蔽选中--><script>document.onselectstart = function (event) {if (window.event) {event = window.event;} try {var the = event.srcElement;if (!((the.tagName == "INPUT" && the.type.toLowerCase() == "text") || the.tagName == "TEXTAREA")) {return false;}return true;} catch (e) {return false;}}</script>

直接去掉这段js，保存源码文件，在浏览器中打开：