Examine source code of YNAB Amazon-Linker

{
  "manifest_version": 3,
  "name": "YNAB Amazon-Linker",
  "version": "0.2.0",
  "description": "Turns Amazon order numbers in YNAB memos into clickable order detail links.",
  "icons": {
    "48": "icon48.png",
    "128": "icon128.png"
  },
  "content_scripts": [
    {
      "matches": [
        "https://app.ynab.com/*"
      ],
      "js": [
        "content.js"
      ],
      "css": [
        "styles.css"
      ],
      "run_at": "document_idle"
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "ynab-amazon-linker@example.com"
    }
  },
  "permissions": []
}