Examine source code of AudioCursor

{
  "manifest_version": 2,
  "name": "AudioCursor",
  "version": "1.0",
  "description": "Hover over words or images to hear context sounds (e.g., 'fire' -> crackle, 'water' -> water-splash). Synthesized with Web Audio.",
  "icons": {
    "48": "icon-48.png",
    "128": "icon-128.png"
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "content_script.js"
      ],
      "run_at": "document_idle"
    }
  ],
  "permissions": [
    "<all_urls>"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{4927ac88-a101-43df-a205-4d71e98ee4e4}"
    }
  }
}