Examine source code of Website Time Manager

{
  "manifest_version": 3,
  "name": "Tab Time Limiter",
  "version": "0.1.0",
  "description": "Limit daily time spent on distracting websites, with session-based budgets.",
  "browser_specific_settings": {
    "gecko": {
      "id": "tab-time-limiter@clement-herve.local",
      "strict_min_version": "115.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    },
    "gecko_android": {
      "strict_min_version": "115.0"
    }
  },
  "background": {
    "scripts": [
      "background.js"
    ],
    "persistent": false
  },
  "action": {
    "default_title": "Tab Time Limiter",
    "default_popup": "popup.html",
    "default_icon": {
      "16": "icons/icon-16.png",
      "32": "icons/icon-32.png",
      "48": "icons/icon-48.png",
      "128": "icons/icon-128.png"
    }
  },
  "options_ui": {
    "page": "options.html",
    "open_in_tab": true
  },
  "icons": {
    "16": "icons/icon-16.png",
    "32": "icons/icon-32.png",
    "48": "icons/icon-48.png",
    "128": "icons/icon-128.png"
  },
  "permissions": [
    "storage",
    "alarms",
    "webRequest",
    "webRequestBlocking"
  ],
  "host_permissions": [
    "<all_urls>"
  ],
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "content-script.js"
      ],
      "run_at": "document_idle",
      "all_frames": false
    }
  ]
}