Examine source code of Fitness Pause Reminder

{
  "manifest_version": 2,
  "name": "Fitness Pause Reminder",
  "version": "1.0",
  "description": "Reminds you to take fitness breaks during work.",
  "icons": {
    "16": "icons/icon16.png",
    "32": "icons/icon32.png",
    "48": "icons/icon48.png",
    "128": "icons/icon128.png"
  },
  "permissions": [
    "storage",
    "alarms",
    "notifications"
  ],
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "options_ui": {
    "page": "options.html",
    "browser_style": true
  },
  "browser_action": {
    "default_icon": {
      "16": "icons/icon16.png",
      "32": "icons/icon32.png",
      "48": "icons/icon48.png",
      "128": "icons/icon128.png"
    },
    "default_title": "Fitness Pause Reminder"
  },
  "browser_specific_settings": {
    "gecko": {
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      },
      "id": "{73ea69b5-b8f0-4615-a027-57a34e6a5f2f}"
    }
  },
  "web_accessible_resources": [
    "sounds/*.mp3",
    "alert.html",
    "alert.js"
  ]
}