redmine 粘贴截屏插件对ie8不兼容

公司最近用redmine，需要加入image_clipboard_paste插件完善截屏粘贴功能
但是这个插件只能支持火狐和谷歌浏览器，对于一个传统软件公司，还有好多用户
必须使用ie8或者更低的版本，所以粘贴截屏功能还必须兼容ie8。经过几天的调试，
发现是js文件中addEventListener和removeEventLitsener方法对ie8不兼容，故将
这两个方法换成了attachEvent和detachEvent方法，但实际情况发现这样修改后
剪切板可以正常显示，但是截屏后ctrl+v没有任何反应，急求大神指点！！！

更改后代码如下：

 var pasteCatcher;

  function initPasteListener() {
    // We start by checking if the browser supports the
    // Clipboard object. If not, we need to create a
    // contenteditable element that catches all pasted data
    if (!window.Clipboard) {
      pasteCatcher = document.createElement("div");

      // Firefox allows images to be pasted into contenteditable elements
      pasteCatcher.setAttribute("contenteditable", "");
      pasteCatcher.setAttribute("id", "cbp_paste_catcher");

      // We can hide the element and append it to the body,
      dialog.appendChild(pasteCatcher);

      // as long as we make sure it is always in focus
      document.attachEvent("click", focusCatcher);
      setTimeout(focusCatcher, 50);
    }
    // Add the paste event listener
    window.attachEvent("paste", pasteHandler);
  };

  function deinitPasteListener() {
    window.detachEvent("paste", pasteHandler);

    if (pasteCatcher) {
      document.detachEvent("click", focusCatcher);
      dialog.removeChild(pasteCatcher);
      delete pasteCatcher;
    }
  };

给官方反应一下，或者你自己改代码