Examine source code of NotionBooks

{
  "manifest_version": 3,
  "name": "NotionBooks",
  "version": "0.1.0",
  "description": "Save Goodreads book details to Notion.",
  "browser_specific_settings": {
    "gecko": {
      "id": "NotionBooks@iShibi",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  },
  "icons": {
    "16": "icon-16.png",
    "32": "icon-32.png",
    "48": "icon-48.png",
    "64": "icon-64.png",
    "128": "icon-128.png",
    "256": "icon-256.png"
  },
  "action": {
    "default_popup": "popup/popup.html"
  },
  "options_page": "options/options.html",
  "permissions": [
    "storage"
  ],
  "host_permissions": [
    "*://*.goodreads.com/*",
    "https://api.notion.com/*"
  ],
  "background": {
    "type": "module",
    "scripts": [
      "background.js"
    ]
  },
  "content_scripts": [
    {
      "run_at": "document_start",
      "matches": [
        "*://*.goodreads.com/*"
      ],
      "js": [
        "content/isolated.js"
      ]
    },
    {
      "world": "MAIN",
      "matches": [
        "*://*.goodreads.com/*"
      ],
      "js": [
        "content/main.js"
      ]
    }
  ]
}