Examine source code of Allenda Softphone

{
  "manifest_version": 2,
  "name": "Allenda Softphone",
  "version": "0.1.1",
  "description": "Softphone SIP (WSS + WebRTC) integrado ao Firefox - contas, discador, contatos e historico.",
  "icons": {
    "48": "assets/icon-48.png",
    "96": "assets/icon-96.png",
    "128": "assets/icon-128.png"
  },
  "permissions": [
    "storage",
    "notifications",
    "unlimitedStorage"
  ],
  "background": {
    "scripts": [
      "background.js"
    ],
    "persistent": true
  },
  "browser_action": {
    "default_title": "Allenda Softphone",
    "default_icon": "assets/icon-48.png"
  },
  "sidebar_action": {
    "default_title": "Allenda Softphone",
    "default_panel": "sidebar.html",
    "default_icon": "assets/icon-48.png",
    "open_at_install": false
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "allenda-softphone@allenda.local",
      "strict_min_version": "140.0",
      "data_collection_permissions": {
        "required": [
          "authenticationInfo",
          "personalCommunications"
        ]
      }
    }
  },
  "content_security_policy": "script-src 'self'; object-src 'self'"
}