Examine source code of Webex Calling

{
  "manifest_version": 2,
  "name": "Webex Calling",
  "version": "1.0",
  "description": "",
  "permissions": [
    "tabs"
  ],
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "browser_action": {
    "default_icon": "icons/icon.png",
    "default_title": "Webex Calling"
  },
  "icons": {
    "48": "icons/icon.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{3835a42d-7fb9-4937-9bad-31909379770d}"
    }
  }
}