Examine source code of Price History

{
  "manifest_version": 2,
  "name": "Price History",
  "version": "0.3resigned1",
  "description": "This extension shows a price history chart for Ukrainian online shops like Rozetka, Moyo, Allo, Foxtrot, Eldorado, Comfy, Fotomost, Collar and Jysk",
  "icons": {
    "48": "icon-48.png"
  },
  "background": {
    "page": "background-page.html"
  },
  "content_scripts": [
    {
      "matches": [
        "*://*.rozetka.com.ua/*",
        "*://*.moyo.ua/*",
        "*://*.allo.ua/*",
        "*://*.foxtrot.com.ua/*",
        "*://*.fotomost.com.ua/*",
        "*://*.eldorado.ua/*",
        "*://*.comfy.ua/*",
        "*://*.bycollar.com/*",
        "*://*.jysk.ua/*"
      ],
      "css": [
        "css/price-history.css"
      ],
      "js": [
        "libs/jquery-3.3.1.slim.min.js",
        "libs/chart.min.js",
        "parser.js",
        "content.js"
      ]
    }
  ],
  "permissions": [
    "activeTab",
    "https://price-history-server.herokuapp.com/"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{271bf467-9b40-497a-ade5-060bdbb14801}"
    }
  }
}