Examine source code of AwardTravel

{
  "name": "AwardTravel",
  "description": "Displays points & miles costs for flights on Google Flights and hotel information!",
  "version": "2.0.2",
  "manifest_version": 2,
  "background": {
    "scripts": [
      "background.js"
    ],
    "persistent": false
  },
  "web_accessible_resources": [
    "content.js",
    "hilton.js",
    "hyatt.js",
    "ihg.js",
    "marriott.js"
  ],
  "externally_connectable": {
    "matches": [
      "*://*.awardtravel.co/*"
    ]
  },
  "content_scripts": [
    {
      "matches": [
        "*://www.google.com/travel/flights/search?*",
        "*://www.google.com/travel/flights/booking?*"
      ],
      "js": [
        "content.js"
      ],
      "css": [
        "styles.css"
      ]
    },
    {
      "matches": [
        "https://www.google.com/travel/search?*"
      ],
      "js": [
        "content.js"
      ]
    },
    {
      "matches": [
        "*://www.awardtravel.co/*"
      ],
      "js": [
        "content.js"
      ]
    },
    {
      "matches": [
        "*://*.marriott.com/*"
      ],
      "js": [
        "marriott.js"
      ]
    },
    {
      "matches": [
        "*://*.hyatt.com/*"
      ],
      "js": [
        "hyatt.js"
      ]
    },
    {
      "matches": [
        "*://*.ihg.com/*"
      ],
      "js": [
        "ihg.js"
      ]
    },
    {
      "matches": [
        "*://*.hilton.com/*"
      ],
      "js": [
        "hilton.js"
      ]
    }
  ],
  "permissions": [
    "background",
    "webNavigation",
    "storage"
  ],
  "host_permissions": [
    "*://www.google.com/travel/*",
    "*://*.marriott.com/*",
    "*://*.hyatt.com/*",
    "*://*.ihg.com/*",
    "*://*.hilton.com/*"
  ],
  "browser_action": {
    "default_popup": "popup.html",
    "default_icon": {
      "16": "images/at_frame16.png",
      "32": "images/at_frame32.png",
      "48": "images/at_frame48.png",
      "128": "images/at_frame128.png"
    }
  },
  "icons": {
    "16": "images/at_frame16.png",
    "32": "images/at_frame32.png",
    "48": "images/at_frame48.png",
    "128": "images/at_frame128.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{910a77f9-5784-4d1e-b384-4f55686e4309}"
    }
  }
}