Examine source code of Darts-Master Pro

{
  "manifest_version": 2,
  "name": "DartsMaster Manager Pro",
  "version": "0.2.1",
  "description": "Free offline darts career simulation game.",
  "browser_specific_settings": {
    "gecko": {
      "id": "{9f1c2a34-5678-4bcd-9123-abcdef123456}",
      "strict_min_version": "142.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  },
  "browser_action": {
    "default_popup": "popup.html",
    "default_title": "DartsMaster Pro"
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "content_scripts": [
    {
      "matches": [
        "*://*.autodarts.io/*",
        "*://*.dartcounter.net/*"
      ],
      "js": [
        "content.js"
      ],
      "run_at": "document_end"
    }
  ],
  "permissions": [
    "tabs",
    "storage",
    "*://*.autodarts.io/*",
    "*://*.dartcounter.net/*",
    "*://autodarts.io/*",
    "*://dartcounter.net/*"
  ],
  "web_accessible_resources": [
    "PDC2_TEST.html"
  ]
}