Examine source code of Scroll Breeze

{
  "manifest_version": 2,
  "name": "Scroll Breeze",
  "version": "1.0",
  "description": "Plays wind sound when you scroll long pages. Wind intensity follows scroll speed.",
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "content.js"
      ],
      "run_at": "document_idle"
    }
  ],
  "icons": {
    "48": "icons/icon48.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{9d479d7f-4716-427b-9b6a-3923b5d95a19}"
    }
  }
}