Examine source code of Media Speed Up

{
  "manifest_version": 2,
  "name": "Media SpeedUp",
  "version": "1.1",
  "description": "動画を高速再生します",
  "icons": {
    "48": "icons/icon48.png",
    "96": "icons/icon96.png"
  },
  "permissions": [
    "activeTab"
  ],
  "browser_action": {
    "default_icon": "icons/icon32.png",
    "default_title": "Media SpeedUp",
    "default_popup": "popup/choose_speedup.html"
  }
}