Examine source code of Voipplay Web Dial

{
  "background": {
    "scripts": [
      "jquery-3.3.1.min.js",
      "background.js"
    ]
  },
  "browser_action": {
    "default_icon": "vp.png",
    "default_popup": "popup.html"
  },
  "content_scripts": [
    {
      "js": [
        "phonelinks.js"
      ],
      "matches": [
        "http://*/*",
        "https://*/*"
      ],
      "run_at": "document_end"
    }
  ],
  "description": "Elk nummer op eender welke website wordt clickable. Heel eenvoudig uitbellen dus. Tijdswinst & efficiëntie gegarandeerd!",
  "manifest_version": 2,
  "name": "Voipplay Web Dial",
  "permissions": [
    "activeTab",
    "contextMenus",
    "notifications",
    "storage",
    "webRequest",
    "*://app.teamleader.eu/*",
    "tabs"
  ],
  "version": "0.3.0.2resigned1",
  "web_accessible_resources": [
    "inject.js"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{d68c4169-a57b-4b60-9c96-5dde4c13c10e}"
    }
  }
}