Examine source code of WebBT

{
  "name": "WebBT",
  "description": "Web Bluetooth API Polyfill for Firefox",
  "author": "Steven Nyman",
  "homepage_url": "https://github.com/stevennyman/webbt",
  "icons": {
    "16": "logo.svg",
    "32": "logo.svg",
    "64": "logo.svg",
    "128": "logo.svg"
  },
  "permissions": [
    "nativeMessaging",
    "storage",
    "https://*/",
    "http://localhost/*",
    "http://127.0.0.1/*"
  ],
  "background": {
    "scripts": [
      "gatt-services.js",
      "gatt-characteristics.js",
      "gatt-descriptors.js",
      "gatt-appearances.js",
      "company-identifiers.js",
      "background.js"
    ]
  },
  "web_accessible_resources": [
    "gatt-services.js",
    "gatt-characteristics.js",
    "gatt-descriptors.js",
    "polyfill.js",
    "options.html"
  ],
  "content_scripts": [
    {
      "matches": [
        "https://*/*",
        "http://localhost/*",
        "http://127.0.0.1/*"
      ],
      "js": [
        "content.js"
      ],
      "all_frames": true,
      "run_at": "document_start"
    },
    {
      "matches": [
        "https://*/*",
        "http://localhost/*",
        "http://127.0.0.1/*"
      ],
      "js": [
        "gatt-services.js",
        "gatt-characteristics.js",
        "gatt-descriptors.js",
        "polyfill.js"
      ],
      "all_frames": true,
      "run_at": "document_start",
      "world": "MAIN"
    }
  ],
  "browser_action": {
    "default_title": "WebBT"
  },
  "options_ui": {
    "page": "options.html"
  },
  "version": "0.6.0",
  "manifest_version": 2,
  "browser_specific_settings": {
    "gecko": {
      "id": "webbt@ff",
      "strict_min_version": "128.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  }
}