Examine source code of Site Powered By

{
  "applications": {
    "gecko": {
      "id": "dai@sitepoweredby.com"
    }
  },
  "manifest_version": 2,
  "name": "Site Powered By",
  "description": "Find tech stack",
  "homepage_url": "https://sitepoweredby.com/",
  "icons": {
    "32": "icons/32x32.png",
    "48": "icons/48x48.png"
  },
  "version": "1.0.0",
  "browser_action": {
    "default_icon": "icons/48x48.png",
    "default_popup": "popup.html",
    "default_title": "Find tech stack"
  },
  "permissions": [
    "*://sitepoweredby.com/*",
    "webRequest",
    "tabs"
  ]
}