Examine source code of Simple Auto Page Reload

{
  "manifest_version": 2,
  "name": "Page Reload",
  "version": "1.1.1",
  "description": "Auto-reload configured URLs on a schedule. Opens them at startup and shows a live countdown in the toolbar popup.",
  "browser_specific_settings": {
    "gecko": {
      "id": "page-reload@katmoda.com",
      "strict_min_version": "140.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    },
    "gecko_android": {
      "strict_min_version": "142.0"
    }
  },
  "permissions": [
    "storage",
    "tabs"
  ],
  "background": {
    "scripts": [
      "background.js"
    ],
    "persistent": true
  },
  "browser_action": {
    "default_title": "Page Reload",
    "default_popup": "popup/popup.html",
    "default_icon": "icons/icon-on-light.svg",
    "theme_icons": [
      {
        "light": "icons/icon-on-dark.svg",
        "dark": "icons/icon-on-light.svg",
        "size": 32
      }
    ]
  },
  "icons": {
    "48": "icons/icon-128.svg",
    "96": "icons/icon-128.svg",
    "128": "icons/icon-128.svg"
  }
}