为什么广告拦截器会阻止 Blob？

Question

如果内容是 blob，广告拦截器会阻止所有打开的新标签页。我认为这背后有一些原因，但我无法弄清楚。我不认为 blob 有什么特别不安全的地方，或者浏览器本身会阻止它们，所以 为什么 广告拦截器甚至没有给你查看它的选项就这样做了？

这是一个 fiddle，因为它不能正确使用 Stack Overflows 代码片段：

https://jsfiddle.net/Pharylon/dqjtha81/32/

const myString = "Hello World!";
const blob = new Blob([myString], {
  type: 'text/plain'
});
const fileURL = URL.createObjectURL(blob);
const myLink = document.getElementById("blob-link");
myLink.setAttribute("href", fileURL);
myLink.style.display = "block";

document.getElementById("my-div").innerText = myLink;

<p>
  The following won't open if you have an adblocker:
</p>

<a style="display: none" id="blob-link" href="" target="_blank">Click Me!</a>

<p>
  But you can manually copy/paste this and it'll work:
</p>

<div id="my-div"></div>

https://jsfiddle.net/Pharylon/dqjtha81/32/

同样，我的问题是为什么 拦截器会这样做。谢谢！

Answer 1

这是 easylist.txt 中的解释，一个流行的阻止列表：

! Used with many websites to generate multiple popups
|blob:$popup
|data:text$popup
|dddata:text$popup

uBlock Origin 的输出中也提到了这一点，它使用了 easylist（以及其他）：

举个具体的例子，其中 blob 与 WebSockets 结合使用 bypass all adblockers at that time, see the code snippet from the uBlock Origin issue（仅重新格式化）：

AdDelivery.prototype.createWW = function() {
    var b = "self.onmessage=function(a){
    self.debug = " + this.debug + ';self.wsurl="
    ' + this.websocketURL + '
    ";self.initWS=

    function(b) {
        self.ws = new WebSocket(b);
        self.ws.onerror = function(c) {
            self.log(
                "Websocket error: " + c);
            postMessage(null)
        };
        self.ws.onopen = function(c) {
            self.log("Websocket connected")
        };
        self.ws.onmessage = function(c) {
            self.log("Websocket received msg.");
            postMessage(c.data)
        }
    };
    self.requestAds = function(b) {
        if (self.ws.readyState !== 1) {
            setTimeout(function() {
                self.log("Waiting for connection");
                self.requestAds(b)
            }, 100)
        } else {
            ws.send(b)
        }
    };
    self.log = function(b) {
        if (self.debug) {
            console.log(b)
        }
    };
    if (!self.ws) {
        self.initWS(self.wsurl);
        self.log("Initializing websocket")
    } else {
        self.log("Websocket already connected")
    }
    self.requestAds(a.data)
};
';
this.blob = new Blob([b], { type: "application/javascript" });
this.ww = new Worker(URL.createObjectURL(this.blob)); return };

为什么广告拦截器会阻止 Blob？

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