Examine source code of Blurrr WhatsApp

{
  "manifest_version": 2,
  "name": "Blurrr WhatsApp",
  "version": "1.0",
  "description": "Hides whatsapp chats and messages",
  "icons": {
    "48": "icon.png"
  },
  "content_scripts": [
    {
      "matches": [
        "*://web.whatsapp.com/*"
      ],
      "css": [
        "index.css"
      ]
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{f3c34444-ec86-454d-9989-7695861947da}"
    }
  }
}