Examine source code of YT Booster

{
  "manifest_version": 2,
  "name": "YT Booster",
  "version": "0.0.0.1",
  "description": "Adds new YouTube tools.",
  "icons": {
    "16": "images/icons/icon-ytbooster16.png",
    "32": "images/icons/icon-ytbooster32.png",
    "48": "images/icons/icon-ytbooster48.png",
    "128": "images/icons/icon-ytbooster128.png"
  },
  "browser_action": {
    "default_icon": "images/icons/icon-ytbooster32.png",
    "default_title": "YT Booster",
    "default_popup": "popup/ytbooster_popup.html"
  },
  "permissions": [
    "unlimitedStorage",
    "downloads",
    "tabs",
    "notifications"
  ],
  "web_accessible_resources": [
    "images/*",
    "images/icons/*",
    "css/*.css",
    "popup/privacy.html"
  ],
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "content_scripts": [
    {
      "matches": [
        "https://www.youtube.com/watch*"
      ],
      "js": [
        "scripts/ytboosterGlobal.js",
        "content.js"
      ]
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{e8f80f24-387a-4f24-9baf-d0b0aa2e7e1c}"
    }
  }
}