Examine source code of Google Input Injector

{
  "manifest_version": 2,
  "name": "Google Input Injector",
  "version": "1.0",
  "description": "Adds a small input field on google.com",
  "content_scripts": [
    {
      "matches": [
        "https://www.google.com/*"
      ],
      "js": [
        "content.js"
      ],
      "run_at": "document_idle"
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{325a5b63-b078-4b29-b8ff-429cb677fa77}"
    }
  }
}