Examine source code of Futbin Plus

{
  "manifest_version": 3,
  "name": "Futbin Plus",
  "version": "1.0",
  "description": "Adding some features to Futbin",
  "author": "Nasser Alrayes",
  "icons": {
    "16": "/assets/icon_16x16.png",
    "48": "/assets/icon_48x48.png",
    "128": "/assets/icon_128x128.png"
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "main.js"
      ]
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "i.n4sser@gmail.com",
      "strict_min_version": "52.0"
    }
  }
}