Examine source code of SheetsMenu

{
  "manifest_version": 3,
  "name": "SheetsMenu",
  "version": "1.0.4",
  "description": "Drag Google Sheets tabs onto each other to create nested hover menus for quick multi-level navigation.",
  "permissions": [
    "storage"
  ],
  "host_permissions": [
    "https://docs.google.com/spreadsheets/*"
  ],
  "content_scripts": [
    {
      "matches": [
        "https://docs.google.com/spreadsheets/*"
      ],
      "js": [
        "content.js"
      ],
      "css": [
        "content.css"
      ],
      "run_at": "document_idle"
    }
  ],
  "action": {
    "default_popup": "popup/popup.html",
    "default_title": "SheetsMenu",
    "default_icon": {
      "16": "icons/icon-16.png",
      "48": "icons/icon-48.png",
      "128": "icons/icon-128.png"
    }
  },
  "icons": {
    "16": "icons/icon-16.png",
    "48": "icons/icon-48.png",
    "128": "icons/icon-128.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "sheets-menu@sheets-menu",
      "strict_min_version": "142.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ],
        "optional": []
      }
    }
  }
}