Examine source code of Focus Break Manager

{
  "manifest_version": 2,
  "name": "Focus Break Manager",
  "version": "1.0",
  "description": "Stay productive by scheduling focus sessions and breaks.",
  "permissions": [
    "notifications",
    "alarms"
  ],
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "browser_action": {
    "default_popup": "popup.html",
    "default_icon": {
      "48": "icon.png"
    }
  },
  "icons": {
    "48": "icon.png"
  },
  "applications": {
    "gecko": {
      "id": "focusbreakmanager@example.com"
    }
  }
}