Examine source code of Website Blocker

{
  "manifest_version": 2,
  "name": "Website Blocker",
  "description": "Block distracting websites with scheduled rules and usage stats",
  "version": "1.0.7",
  "icons": {
    "16": "icon16.png",
    "32": "icon32.png",
    "48": "icon48.png",
    "128": "icon128.png"
  },
  "permissions": [
    "declarativeNetRequest",
    "storage",
    "alarms",
    "tabs",
    "http://*/*",
    "https://*/*"
  ],
  "web_accessible_resources": [
    "blocked.html"
  ],
  "browser_specific_settings": {
    "gecko": {
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      },
      "id": "{1334cbe5-f3ec-4df2-89c7-e7ac7bbf1985}"
    }
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "browser_action": {
    "default_popup": "popup.html"
  }
}