Fix github ipynb render failed

Patch addEventListener to drop window message events except {type:'render'}

You will need to install an extension such as Tampermonkey, Greasemonkey or Violentmonkey to install this script.

You will need to install an extension such as Tampermonkey to install this script.

You will need to install an extension such as Tampermonkey or Violentmonkey to install this script.

You will need to install an extension such as Tampermonkey or Userscripts to install this script.

You will need to install an extension such as Tampermonkey to install this script.

You will need to install a user script manager extension to install this script.

(У мене вже є менеджер скриптів, дайте мені встановити його!)

You will need to install an extension such as Stylus to install this style.

You will need to install an extension such as Stylus to install this style.

You will need to install an extension such as Stylus to install this style.

You will need to install a user style manager extension to install this style.

You will need to install a user style manager extension to install this style.

You will need to install a user style manager extension to install this style.

(I already have a user style manager, let me install it!)

// ==UserScript==
// @name         Fix github ipynb render failed
// @namespace    https://tampermonkey.net/
// @version      0.1.0
// @description  Patch addEventListener to drop window message events except {type:'render'}
// @author       plusls
// @include      *://github.com/*
// @run-at       document-start
// @grant        none
// @license MIT
// ==/UserScript==

(function () {
  'use strict';

  const origAdd = EventTarget.prototype.addEventListener;
  const origRemove = EventTarget.prototype.removeEventListener;

  // 关键:缓存包装后的函数,避免重复包装 & 保证 removeEventListener 能移除
  const wrappedMap = new WeakMap();

  function shouldDropMessageEvent(message_event) {
    const data = message_event && message_event.data;
    // drop no render event
    return data.type && data.type !== 'render';
  }

  EventTarget.prototype.addEventListener = function (...args) {
    const [type, listener] = args;

    if (type === 'message' && typeof listener === 'function') {
      // 同一个 listener 只包装一次
      let wrapped = wrappedMap.get(listener);
      if (!wrapped) {
        wrapped = function (message_event) {
          if (shouldDropMessageEvent(message_event)) {
            // console.log('drop event');
            // console.log(message_event);
            return;
          }
          return listener.call(this, message_event);
        };
        wrappedMap.set(listener, wrapped);
      }

      args[1] = wrapped;
    }

    return origAdd.apply(this, args);
  };

  // 可选但强烈建议:同步修补 removeEventListener,确保能正常移除
  EventTarget.prototype.removeEventListener = function (...args) {
    const [type, listener] = args;

    if (type === 'message' && typeof listener === 'function') {
      const wrapped = wrappedMap.get(listener);
      if (wrapped) args[1] = wrapped;
    }

    return origRemove.apply(this, args);
  };
})();