Examine source code of Coffee Break Timer

{
  "manifest_version": 2,
  "name": "Coffee Break Timer",
  "version": "1.0",
  "description": "Set a timer for coffee and short breaks.",
  "permissions": [
    "storage",
    "notifications"
  ],
  "background": {
    "scripts": [
      "background.js"
    ],
    "persistent": false
  },
  "browser_action": {
    "default_icon": "icon.png",
    "default_title": "Coffee Break Timer",
    "default_popup": "popup.html"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{dcdc61ec-eb24-4d8f-81f9-fd8c68d5e36d}"
    }
  }
}