Examine source code of YouTube Simplified

{
  "manifest_version": 2,
  "name": "YouTube Simplified",
  "version": "1.1",
  "description": "Disables various features on YouTube",
  "permissions": [
    "storage"
  ],
  "browser_action": {
    "default_popup": "options-panel/options.htm"
  },
  "content_scripts": [
    {
      "matches": [
        "*://*.youtube.com/*"
      ],
      "js": [
        "features.js",
        "main.js"
      ],
      "css": [
        "main.css"
      ]
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{f2d26df3-8769-4e4a-abc5-f695675da936}"
    }
  }
}