Examine source code of Travel Back

{
  "manifest_version": 2,
  "name": "Travel Back",
  "version": "1.2.0",
  "description": "Automatically link your Booking.com bookings to Travel Back and earn rewards on every trip - install once, browse as usual, no extra steps.",
  "icons": {
    "48": "icons/icon-48.png",
    "96": "icons/icon-96.png"
  },
  "permissions": [
    "storage",
    "tabs",
    "webRequest",
    "webRequestBlocking",
    "*://booking.com/*",
    "*://www.booking.com/*",
    "*://*.booking.com/*"
  ],
  "background": {
    "scripts": [
      "tracking-config.js",
      "tracking.js",
      "background/background.js"
    ]
  },
  "options_ui": {
    "page": "options/options.html"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "official@tabtravel"
    }
  }
}