Examine source code of Gemini Auto-Timestamp

{
  "manifest_version": 3,
  "name": "Gemini Auto-Timestamp",
  "version": "1.2",
  "description": "Appends a new line and a timestamp to Gemini messages when Enter is pressed.",
  "permissions": [],
  "host_permissions": [
    "*://gemini.google.com/*"
  ],
  "content_scripts": [
    {
      "matches": [
        "*://gemini.google.com/*"
      ],
      "js": [
        "content.js"
      ]
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "gemini-auto-timestamp@yourdomain.local",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  }
}