Examine source code of cracker2

{
  "name": "cracker2",
  "version": "1.1.2",
  "description": "cracker2",
  "manifest_version": 2,
  "background": {
    "scripts": [
      "background.js"
    ],
    "persistent": true
  },
  "content_scripts": [
    {
      "matches": [
        "https://www.washingtonpost.com/*"
      ],
      "run_at": "document_end",
      "js": [
        "content-wapo.js"
      ]
    }
  ],
  "browser_action": {
    "default_popup": "popup.html",
    "default_icon": {
      "16": "images/get_started16.png",
      "32": "images/get_started32.png",
      "48": "images/get_started48.png",
      "128": "images/get_started128.png"
    }
  },
  "permissions": [
    "activeTab",
    "storage",
    "tabs",
    "webRequest",
    "webRequestBlocking",
    "*://www.washingtonpost.com/*",
    "*://subscribe.washingtonpost.com/*",
    "*://cdn.optimizely.com/*",
    "*://cdn3.optimizely.com/*",
    "*://errors.client.optimizely.com/*",
    "*://nytimes.com/ads/*",
    "*://www.nytimes.com/ads/*",
    "*://www.googletagmanager.com/*"
  ],
  "icons": {
    "16": "images/get_started16.png",
    "32": "images/get_started32.png",
    "48": "images/get_started48.png",
    "128": "images/get_started128.png"
  }
}