Examine source code of YouTube Real Duration

{
  "manifest_version": 2,
  "name": "youtubeRealTime",
  "version": "1.1",
  "description": "Updates sped up / slowed down YouTube videos to indicate their real duration.",
  "icons": {
    "48": "icons/icon.png"
  },
  "content_scripts": [
    {
      "matches": [
        "https://www.youtube.com/*"
      ],
      "js": [
        "youtubeRealTime.js",
        "jquery.js"
      ]
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{be2d4624-2900-4a86-bad4-7bae1005b268}"
    }
  }
}