Examine source code of Enhance YouTube playback

{
  "manifest_version": 2,
  "name": "Magic Actions for YouTube — Lite",
  "version": "1.0.0",
  "description": "Lightweight Magic Actions for YouTube: Cinema mode, Auto HD (best-effort), and mouse-wheel volume. Local-only.",
  "permissions": [
    "activeTab",
    "tabs",
    "storage"
  ],
  "background": {
    "scripts": [
      "background.js"
    ],
    "persistent": false
  },
  "browser_action": {
    "default_title": "Magic Actions for YouTube",
    "default_popup": "popup.html"
  },
  "content_scripts": [
    {
      "matches": [
        "*://www.youtube.com/*",
        "*://youtube.com/*"
      ],
      "js": [
        "content_script.js"
      ],
      "run_at": "document_idle"
    }
  ],
  "applications": {
    "gecko": {
      "id": "magic-actions-youtube-lite@example.com",
      "strict_min_version": "60.0"
    }
  }
}