Examine source code of YouTube Resolution Setter

{
  "manifest_version": 2,
  "name": "YouTube Resolution Setter",
  "version": "1.0",
  "description": "Set and save your preferred YouTube video resolution.",
  "background": {
    "scripts": [
      "popup.js"
    ],
    "persistent": false
  },
  "browser_action": {
    "default_popup": "popup.html",
    "default_icon": "icon.png"
  },
  "permissions": [
    "activeTab",
    "storage"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{90ad3835-90e1-49ab-a7f4-a12857818ab1}"
    }
  }
}