Examine source code of Focus Police

{
  "manifest_version": 2,
  "name": "Focus Police",
  "version": "2.0",
  "description": "Boost productivity by blocking distracting sites. Includes Pomodoro timer, funny block messages, and strict focus modes.",
  "permissions": [
    "storage",
    "tabs",
    "alarms",
    "notifications",
    "webRequest",
    "webRequestBlocking"
  ],
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "browser_action": {
    "default_popup": "popup.html",
    "default_title": "Focus Police",
    "default_icon": {
      "16": "images/icon16.png",
      "48": "images/icon48.png",
      "128": "images/icon128.png"
    }
  },
  "icons": {
    "16": "images/icon16.png",
    "48": "images/icon48.png",
    "128": "images/icon128.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "focuspolice@example.com",
      "strict_min_version": "90.0"
    }
  }
}