Examine source code of Nudgeti

{
  "manifest_version": 2,
  "name": "Nudgeti - Website Blocker Alternative",
  "description": "Don't waste time on distracting websites. A gentler alternative to website blockers.",
  "version": "0.4.3",
  "icons": {
    "16": "images/nudgeti-16.png",
    "48": "images/nudgeti-48.png",
    "128": "images/nudgeti-128.png"
  },
  "permissions": [
    "tabs",
    "notifications",
    "alarms",
    "storage"
  ],
  "applications": {
    "gecko": {
      "id": "{8d602839-c5f4-4ef4-ad5d-216489973284}",
      "strict_min_version": "42.0"
    }
  },
  "background": {
    "scripts": [
      "util/polyfill.js",
      "util/store.js",
      "core/settings-store.js",
      "core/sound.js",
      "core/nudgeti.js"
    ]
  },
  "options_ui": {
    "page": "settings/settings.html"
  }
}