Examine source code of MiniLyrics Hover

{
  "manifest_version": 2,
  "name": "MiniLyrics Hover",
  "version": "1.0",
  "description": "Show current lyric snippet when hovering near the top of the page (simulates tab hover). Auto-syncs with media timeupdate if page exposes media and LRC lyrics or user-provided.",
  "icons": {
    "48": "icon-48.png",
    "128": "icon-128.png"
  },
  "permissions": [
    "storage",
    "tabs",
    "activeTab",
    "<all_urls>"
  ],
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "content_script.js"
      ],
      "run_at": "document_idle"
    }
  ],
  "browser_action": {
    "default_title": "MiniLyrics Hover",
    "default_popup": "popup.html"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{0be64609-9fdd-4c12-a006-163ce7fa5fc8}"
    }
  }
}