Examine source code of WS Remote YT Controller

{
  "manifest_version": 3,
  "name": "WS Remote",
  "version": "1.0",
  "permissions": [
    "scripting",
    "activeTab"
  ],
  "host_permissions": [
    "ws://localhost/*",
    "ws://127.0.0.1/*"
  ],
  "content_scripts": [
    {
      "matches": [
        "*://*.youtube.com/*"
      ],
      "js": [
        "content.js"
      ]
    }
  ],
  "action": {
    "default_popup": "popup.html"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "ws-remote@nabaraj-bhandari.com.np"
    }
  }
}