Examine source code of WhatsApp Direct Message

{
  "manifest_version": 2,
  "name": "__MSG_appName__",
  "version": "1.7",
  "description": "__MSG_appDescription__",
  "default_locale": "en",
  "browser_action": {
    "default_popup": "src/index.html",
    "default_icon": {
      "16": "src/images/icons/icon-16.png",
      "32": "src/images/icons/icon-32.png",
      "36": "src/images/icons/icon-36.png",
      "48": "src/images/icons/icon-48.png",
      "57": "src/images/icons/icon-57.png",
      "60": "src/images/icons/icon-60.png",
      "70": "src/images/icons/icon-70.png",
      "72": "src/images/icons/icon-72.png",
      "76": "src/images/icons/icon-76.png",
      "96": "src/images/icons/icon-96.png",
      "120": "src/images/icons/icon-120.png",
      "144": "src/images/icons/icon-144.png",
      "150": "src/images/icons/icon-150.png",
      "152": "src/images/icons/icon-152.png",
      "180": "src/images/icons/icon-180.png",
      "192": "src/images/icons/icon-192.png",
      "310": "src/images/icons/icon-310.png"
    }
  },
  "icons": {
    "16": "src/images/icons/icon-16.png",
    "32": "src/images/icons/icon-32.png",
    "36": "src/images/icons/icon-36.png",
    "48": "src/images/icons/icon-48.png",
    "57": "src/images/icons/icon-57.png",
    "60": "src/images/icons/icon-60.png",
    "70": "src/images/icons/icon-70.png",
    "72": "src/images/icons/icon-72.png",
    "76": "src/images/icons/icon-76.png",
    "96": "src/images/icons/icon-96.png",
    "120": "src/images/icons/icon-120.png",
    "144": "src/images/icons/icon-144.png",
    "150": "src/images/icons/icon-150.png",
    "152": "src/images/icons/icon-152.png",
    "180": "src/images/icons/icon-180.png",
    "192": "src/images/icons/icon-192.png",
    "310": "src/images/icons/icon-310.png"
  },
  "content_scripts": [
    {
      "matches": [
        "*://*.whatsapp.com/*"
      ],
      "js": [
        "dist/scripts/script.min.js"
      ]
    }
  ],
  "permissions": [
    "storage",
    "tabs"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "wadm@elcreative.com"
    }
  }
}