Examine source code of TubeControl

{
  "manifest_version": 2,
  "name": "YouControl",
  "version": "1.9",
  "description": "Hides youtube recommandations until the user reaches for it.",
  "icons": {
    "96": "icons/24dpicon.png"
  },
  "content_scripts": [
    {
      "matches": [
        "*://*.youtube.com/*"
      ],
      "js": [
        "youcontrol.js"
      ]
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{08d1e65f-7fff-4fbc-b816-dd82323f2dfa}",
      "data_collection_permissions": {
        "required": [
          "websiteContent"
        ],
        "optional": []
      }
    }
  }
}