Examine source code of Metastream Remote

{
  "name": "Metastream Remote",
  "short_name": "Metastream",
  "version": "2.4.0",
  "description": "Watch streaming media with friends.",
  "icons": {
    "16": "icon16.png",
    "48": "icon48.png",
    "128": "icon128.png"
  },
  "action": {
    "default_icon": "icon48.png"
  },
  "content_scripts": [
    {
      "matches": [
        "https://app.getmetastream.com/*",
        "*://local.getmetastream.com/*",
        "*://127.0.0.1/*",
        "*://localhost/*"
      ],
      "js": [
        "app.js"
      ],
      "run_at": "document_start"
    }
  ],
  "host_permissions": [
    "<all_urls>"
  ],
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "manifest_version": 3,
  "browser_specific_settings": {
    "gecko": {
      "id": "{da2b93f0-35d5-461e-9bc7-6ba10aef1af4}",
      "strict_min_version": "142.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  },
  "permissions": [
    "tabs",
    "declarativeNetRequest",
    "webNavigation",
    "webRequest",
    "contextMenus",
    "scripting",
    "storage"
  ],
  "optional_permissions": []
}