Examine source code of StayProductive

{
  "manifest_version": 2,
  "name": "StayProductive",
  "version": "2.3.0",
  "description": "“Focus on being productive instead of busy.” - Tim Ferriss",
  "icons": {
    "64": "icons/productive-48.png"
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "options_ui": {
    "page": "options.html"
  },
  "browser_action": {
    "default_title": "StayProductive",
    "default_icon": {
      "64": "icons/productive-48.png"
    },
    "default_popup": "pomodoro.html"
  },
  "permissions": [
    "storage",
    "notifications",
    "tabs",
    "alarms"
  ],
  "optional_permissions": [
    "downloads"
  ]
}