Examine source code of BreakWise — Eye & Posture Break Reminder

{
  "manifest_version": 3,
  "name": "BreakWise — Eye & Posture Break Reminder",
  "version": "2.0.0",
  "description": "Forces eye breaks every 20 min using the 20-20-20 rule. Full-screen overlay, streak tracking, posture reminders. Free.",
  "permissions": [
    "storage",
    "alarms",
    "notifications"
  ],
  "background": {
    "scripts": [
      "background.js"
    ],
    "service_worker": "background.js"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "breakwise@breakwise.netlify.app",
      "strict_min_version": "140.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  },
  "action": {
    "default_popup": "popup.html",
    "default_icon": {
      "16": "icons/icon16.png",
      "48": "icons/icon48.png",
      "128": "icons/icon128.png"
    }
  },
  "options_page": "options.html",
  "icons": {
    "16": "icons/icon16.png",
    "48": "icons/icon48.png",
    "128": "icons/icon128.png"
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "content.js"
      ],
      "css": [
        "overlay.css"
      ]
    }
  ]
}