Examine source code of MIA club

{
  "manifest_version": 2,
  "name": "MIA Club",
  "short_name": "MIA Club",
  "version": "1.3.2resigned1",
  "author": "MIA Club",
  "homepage_url": "https://www.miaclub.cz",
  "icons": {
    "16": "assets/icon16.png",
    "48": "assets/icon48.png",
    "64": "assets/icon64.png",
    "128": "assets/icon128.png"
  },
  "permissions": [
    "http://*/*",
    "https://*/*"
  ],
  "content_scripts": [
    {
      "matches": [
        "*://*/*"
      ],
      "js": [
        "src/miaclub.js"
      ],
      "css": [
        "src/miaclub.css"
      ]
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{6badee0b-7d33-4e13-b690-1a510c5ce6ce}"
    }
  }
}