Examine source code of Help Universe

{
  "manifest_version": 2,
  "name": "Help Universe",
  "author": "morlooy",
  "description": "Lightweight addon which add some UI to default layout with useful information about our empire.",
  "homepage_url": "https://board.origin.ogame.gameforge.com/index.php/Thread/11206-Help-Universe/",
  "version": "1.0",
  "permissions": [
    "unlimitedStorage",
    "storage"
  ],
  "icons": {
    "48": "images/favicon.png"
  },
  "web_accessible_resources": [
    "css/*.css",
    "images/*.gif",
    "images/*.png",
    "images/*.jpg",
    "locale/*.json"
  ],
  "content_scripts": [
    {
      "run_at": "document_start",
      "matches": [
        "*://*.ogame.gameforge.com/game/*"
      ],
      "js": [
        "script.js"
      ],
      "css": [
        "styles.css"
      ]
    }
  ]
}