Examine source code of Panel call

{
  "manifest_version": 2,
  "name": "Panel call",
  "version": "3",
  "description": "Hold-to-buy and hold-to-sell draggable buttons for Sarin orderbook.",
  "content_scripts": [
    {
      "matches": [
        "*://www.saringold.com/user/trading/*",
        "*://saringold.com/user/trading/*"
      ],
      "js": [
        "content.js"
      ],
      "run_at": "document_idle"
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "setinrate-swapper@yourname.dev"
    }
  }
}