Examine source code of RandomUA

{
  "manifest_version": 2,
  "name": "RandomUA",
  "short_name": "RandomUA",
  "author": "Leo Tindall",
  "version": "1.1.1resigned1",
  "developer": {
    "name": "Leo Tindall",
    "url": "https://leotindall.com/randomua/"
  },
  "description": "Switches the user agent of the browser randomly for each new request.",
  "icons": {
    "48": "icons/randomua-48.png",
    "96": "icons/randomua-96.png"
  },
  "permissions": [
    "storage",
    "webRequest",
    "webRequestBlocking",
    "<all_urls>"
  ],
  "options_ui": {
    "page": "pages/prefs.html",
    "browser_style": true
  },
  "background": {
    "scripts": [
      "background/random-ua.js"
    ]
  },
  "applications": {
    "gecko": {
      "id": "{f12d78f2-b4e9-4a3e-9d2a-655fd45f1ab5}"
    }
  }
}