Examine source code of Subscription Tracker

{
  "manifest_version": 2,
  "name": "Subscription Tracker",
  "version": "1.3",
  "description": "Track recurring subscriptions, next billing dates, cost, and get reminders before charge dates.",
  "icons": {
    "32": "icons/logo_32.png",
    "64": "icons/logo_64.png",
    "128": "icons/logo_128.png"
  },
  "permissions": [
    "storage",
    "notifications",
    "alarms",
    "activeTab"
  ],
  "background": {
    "scripts": [
      "background.js"
    ],
    "persistent": false
  },
  "browser_action": {
    "default_title": "Subscription Tracker",
    "default_icon": "icons/logo_64.png",
    "default_popup": "popup.html"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "@Subscription-Tracker",
      "data_collection_permissions": {
        "required": [
          "locationInfo"
        ],
        "optional": [
          "technicalAndInteraction"
        ]
      }
    }
  }
}