Examine source code of Insta Ghost

{
  "name": "Insta Ghost",
  "version": "1.1",
  "manifest_version": 2,
  "description": "A browser extension for Instagram to see stories without seen.",
  "background": {
    "scripts": [
      "script.js"
    ]
  },
  "browser_action": {
    "default_popup": "option.html"
  },
  "permissions": [
    "storage",
    "webRequest",
    "webRequestBlocking",
    "*://*.instagram.com/*"
  ],
  "icons": {
    "16": "logo/logo16.png",
    "48": "logo/logo48.png",
    "128": "logo/logo128.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{e2260d07-e1dc-44a3-a0e1-70080812f4ab}"
    }
  }
}