Examine source code of Auto Tab domain grouper

{
  "manifest_version": 3,
  "name": "Auto Tab Grouping",
  "version": "1.4",
  "description": "Automatically groups tabs by defined rules.",
  "browser_specific_settings": {
    "gecko": {
      "id": "firefoxextensions@salainne.com",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  },
  "icons": {
    "16": "icons/icon16.png",
    "32": "icons/icon32.png",
    "48": "icons/icon48.png",
    "128": "icons/icon128.png"
  },
  "permissions": [
    "tabs",
    "tabGroups",
    "activeTab",
    "storage"
  ],
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "action": {
    "default_popup": "popup.html",
    "default_title": "Auto Tab Grouper",
    "default_icon": {
      "16": "icons/icon16.png",
      "32": "icons/icon32.png",
      "48": "icons/icon48.png",
      "128": "icons/icon128.png"
    }
  },
  "content_security_policy": {
    "extension_pages": "script-src 'self'; object-src 'self'"
  }
}