Examine source code of Focus Lock

{
  "manifest_version": 2,
  "name": "Focus Lock",
  "version": "1.0.2",
  "description": "Block websites for a configurable duration with no early cancellation",
  "browser_specific_settings": {
    "gecko": {
      "id": "{d371ed2a-d508-4827-977d-7492d95bcbe5}",
      "strict_min_version": "142.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  },
  "permissions": [
    "storage",
    "webRequest",
    "webRequestBlocking",
    "<all_urls>",
    "tabs"
  ],
  "background": {
    "scripts": [
      "background.js"
    ],
    "persistent": true
  },
  "browser_action": {
    "default_popup": "popup.html",
    "default_icon": {
      "48": "icon.png"
    },
    "default_title": "Focus Lock"
  },
  "web_accessible_resources": [
    "blocked.html"
  ],
  "icons": {
    "48": "icon.png"
  }
}