Examine source code of 3CX Auto Caller

{
  "manifest_version": 2,
  "name": "3CX Auto Caller",
  "version": "1.0",
  "description": "Automatically clicks the video call button on 3CX web client.",
  "content_scripts": [
    {
      "matches": [
        "https://pbx.mdt.gov.tt/*"
      ],
      "js": [
        "content-script.js"
      ],
      "run_at": "document_end"
    }
  ],
  "permissions": [
    "activeTab"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{5f7a515b-26e5-4e96-84c3-adca9b88b32f}"
    }
  }
}