Examine source code of YouTube Time Blocker

{
  "manifest_version": 2,
  "name": "YouTube Time Blocker",
  "version": "1.0",
  "description": "Blocks access to YouTube during a set time span.",
  "icons": {
    "48": "icon.png"
  },
  "browser_action": {
    "default_popup": "popup.html",
    "default_icon": "icon.png"
  },
  "permissions": [
    "storage",
    "webRequest",
    "webRequestBlocking",
    "*://www.youtube.com/*",
    "*://youtu.be/*"
  ],
  "background": {
    "scripts": [
      "background.js"
    ],
    "persistent": true
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{b2850d74-0729-472c-a6ae-b31ed69f9e4a}"
    }
  }
}