Examine source code of New Tab Cleaner

{
  "manifest_version": 2,
  "name": "New Tab Cleaner",
  "version": "1.0.2",
  "description": "Closes stale new tabs and other new tabs when a new tab is opened.",
  "permissions": [
    "tabs",
    "storage",
    "alarms"
  ],
  "background": {
    "scripts": [
      "background.js"
    ],
    "persistent": false
  },
  "options_ui": {
    "page": "options.html",
    "open_in_tab": false
  },
  "icons": {
    "48": "icons/icon.svg",
    "96": "icons/icon.svg"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "new-tab-cleaner@local",
      "strict_min_version": "140.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ],
        "optional": []
      }
    },
    "gecko_android": {
      "strict_min_version": "142.0"
    }
  }
}