Background Network Requests Indicator

Shows an indicator at bottom right/left when there is one or more background network requests in progress.
当前为 2017-06-05 提交的版本，查看最新版本。
换行
// ==UserScript==
// @name        Background Network Requests Indicator
// @namespace   BackgroundNetworkRequestsIndicator
// @description Shows an indicator at bottom right/left when there is one or more background network requests in progress.
// @version     1.0.1
// @author      jcunews
// @include     *://*/*
// @grant       none
// @run-at      document-start
// ==/UserScript==

(function() {
  var ele = document.createElement("SCRIPT");
  ele.text = "(" + (function() {

    var xhrCount = 0, xhrSend = XMLHttpRequest.prototype.send;
    var eleStyle = "\
display:block!important; opacity:1!important; visibility:visible!important; \
position:fixed!important; z-index:9999999999!important; left:auto!important; \
top:auto!important; right:0!important; bottom:0!important; float:none!important; \
margin:0!important; box-sizing:content-box!important; border:4px solid #bb0!important; \
border-radius:12px!important; padding:0!important; min-width:16px!important; \
background:#ff0!important; text-align:center!important; \
font:12px/16px sans-serif!important";
    var ele = document.createElement("DIV");
    ele.style.cssText = eleStyle;

    function checkCursor(ev) {
      if (ev.clientX >= Math.floor(innerWidth / 2)) {
        ele.style.cssText = eleStyle.replace(/left:auto/, "left:0").replace(/right:0/, "right:auto");
      } else ele.style.cssText = eleStyle;
    }

    ele.onclick = function(){
    ele.style.cssText = eleStyle.replace(/left:auto/, "left:0").replace(/right:0/, "right:auto");
    };
    function xhrDone() {
      if (--xhrCount < 0) xhrCount = 0;
      if (xhrCount) {
        ele.textContent = xhrCount;
      } else {
        removeEventListener("mousemove", checkCursor);
        document.body.removeChild(ele);
      }
    }

    XMLHttpRequest.prototype.send = function() {
      if (!this.indicator) {
        this.addEventListener("error", xhrDone);
        this.addEventListener("load", xhrDone);
        this.indicator = true;
      }
      ele.textContent = ++xhrCount;
      if (!ele.parentNode) {
        document.body.appendChild(ele);
        addEventListener("mousemove", checkCursor);
      }
      return xhrSend.apply(this, arguments);
    };

  }).toString() + ")()";
  document.head.appendChild(ele);
})();