Examine source code of No More Chinese

{
  "name": "No_More_Chinese",
  "version": "1.3resigned1",
  "description": "Close those webpages which contains Chinese.",
  "icons": {
    "16": "icon.png",
    "32": "icon.png",
    "48": "icon.png",
    "128": "icon.png"
  },
  "manifest_version": 2,
  "permissions": [
    "<all_urls>",
    "tabs",
    "activeTab",
    "storage"
  ],
  "browser_action": {
    "default_popup": "popup.html",
    "default_title": "No More Chinese",
    "default_icon": {
      "16": "icon.png",
      "32": "icon.png",
      "48": "icon.png",
      "128": "icon.png"
    }
  },
  "background": {
    "scripts": [
      "background.js"
    ],
    "persistent": true
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "do.js"
      ]
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{eb34d03b-4ce5-40d7-80f0-4083a6d6a6a0}"
    }
  }
}