Examine source code of WebRating

{
  "name": "WebRating",
  "version": "1.0",
  "description": "Rate your websites. Remember the good ones",
  "permissions": [
    "activeTab",
    "storage",
    "tabs",
    "http://*/",
    "https://*/"
  ],
  "background": {
    "page": "background.html",
    "persistent": false
  },
  "browser_action": {
    "default_icon": {
      "16": "images/icon16.png",
      "32": "images/icon32.png",
      "48": "images/icon48.png",
      "128": "images/icon128.png"
    },
    "default_title": "WebRating"
  },
  "content_scripts": [
    {
      "all_frames": false,
      "js": [
        "js/startup.js"
      ],
      "match_about_blank": false,
      "matches": [
        "http://*/*",
        "https://*/*"
      ],
      "run_at": "document_end"
    }
  ],
  "icons": {
    "16": "images/icon16.png",
    "32": "images/icon32.png",
    "48": "images/icon48.png",
    "128": "images/icon128.png"
  },
  "web_accessible_resources": [
    "popup.html"
  ],
  "manifest_version": 2
}