Examine source code of nico-skip

{
  "manifest_version": 2,
  "name": "nico-skip [v0.2.8]",
  "version": "0.2.9",
  "description": "ニコニコ動画で最初にスキップするボタンを追加します。",
  "icons": {
    "32": "icons/icon_x32.png",
    "48": "icons/icon_x48.png",
    "96": "icons/icon_x96.png"
  },
  "content_scripts": [
    {
      "matches": [
        "*://www.nicovideo.jp/watch/*"
      ],
      "js": [
        "seekBarUtils.js",
        "script.js"
      ],
      "css": [
        "style.css"
      ]
    }
  ],
  "web_accessible_resources": [
    "images/loop.png",
    "images/loop2.png"
  ],
  "permissions": [],
  "browser_specific_settings": {
    "gecko": {
      "id": "{1f8037e3-944a-47c8-870f-dc404aec8238}"
    }
  }
}