Examine source code of Enhanced Cardmarket

{
  "manifest_version": 3,
  "name": "Enhanced Cardmarket",
  "version": "0.2.80",
  "description": "Enhanced Cardmarket",
  "icons": {
    "48": "icons/enhanced-cardmarket-48x48.png",
    "141": "icons/enhanced-cardmarket-141x141.png"
  },
  "content_scripts": [
    {
      "matches": [
        "*://*.cardmarket.com/*",
        "*://cardmarket.com/*"
      ],
      "js": [
        "js/lib/browser-polyfill.min.js",
        "js/lib/purify.min.js",
        "js/classes.js",
        "js/include.js",
        "js/cardmarket.js"
      ],
      "css": [
        "css/cardmarket.css"
      ]
    }
  ],
  "permissions": [
    "storage",
    "scripting"
  ],
  "host_permissions": [
    "*://*.cardmarket.com/*",
    "*://cardmarket.com/*",
    "https://api-cardmarket.mave.me/chart"
  ],
  "optional_host_permissions": [
    "https://kaiofcards.com/*",
    "https://www.despelvogel.com/*",
    "https://zycards.nl/*"
  ],
  "action": {},
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "options_ui": {
    "page": "options.html",
    "open_in_tab": true
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "enhanced-cardmarket@mave.me",
      "strict_min_version": "128.0"
    },
    "gecko_android": {
      "id": "enhanced-cardmarket@mave.me",
      "strict_min_version": "128.0"
    }
  }
}