Examine source code of AT Price Tracker

{
  "name": "AT Price Tracker",
  "manifest_version": 2,
  "version": "1.3.1",
  "description": "Show price history on AT UK and track price changes automatically",
  "author": "atpricetrackeraddon@gmail.com",
  "icons": {
    "16": "images/icon16.png",
    "32": "images/icon32.png",
    "48": "images/icon48.png",
    "128": "images/jMBLUwalH7.png"
  },
  "browser_action": {
    "default_popup": "popup.html"
  },
  "permissions": [
    "storage",
    "https://at.liprock.com/"
  ],
  "background": {
    "scripts": [
      "background.min.js"
    ]
  },
  "content_scripts": [
    {
      "matches": [
        "*://*.autotrader.co.uk/*"
      ],
      "js": [
        "contentScript.min.js"
      ],
      "css": [
        "styles.min.css"
      ]
    },
    {
      "matches": [
        "https://at.liprock.com/*"
      ],
      "js": [
        "externalContentScript.min.js"
      ]
    }
  ],
  "web_accessible_resources": [
    "images/jMBLUwalH7.png",
    "images/0F9gawMAFP.svg",
    "images/IHFiljYeve.svg",
    "images/WPQ5cDxrXt.svg",
    "images/3nA0EZQ4h8.svg"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "atpricetrackeraddon@gmail.com"
    }
  }
}