Examine source code of Hydration Reminder

{
  "manifest_version": 2,
  "name": "Hydration Reminder",
  "version": "1.0",
  "description": "Calculate your daily water intake and set reminders to stay hydrated.",
  "icons": {
    "48": "icons/water-icon-48.png"
  },
  "permissions": [],
  "browser_action": {
    "default_icon": "icons/water-icon-48.png",
    "default_popup": "popup.html",
    "default_title": "Hydration Reminder"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{2729954a-eceb-4138-a6ad-c4f519e4dad4}"
    }
  }
}