Examine source code of Alarm, Timer and Stopwatch

{
  "manifest_version": 3,
  "version": "0.3.1",
  "name": "Alarm, Timer and Stopwatch",
  "description": "__MSG_description__",
  "default_locale": "en",
  "permissions": [
    "storage",
    "alarms",
    "idle",
    "contextMenus",
    "offscreen"
  ],
  "offline_enabled": true,
  "homepage_url": "https://webextension.org/listing/alarm.html",
  "background": {
    "service_worker": "worker.js",
    "scripts": [
      "worker.js"
    ]
  },
  "icons": {
    "16": "data/icons/16.png",
    "32": "data/icons/32.png",
    "48": "data/icons/48.png",
    "64": "data/icons/64.png",
    "128": "data/icons/128.png",
    "256": "data/icons/256.png",
    "512": "data/icons/512.png"
  },
  "action": {
    "default_popup": "data/popup/index.html"
  },
  "options_ui": {
    "open_in_tab": true,
    "page": "data/options/index.html"
  },
  "commands": {
    "_execute_action": {},
    "open-interface": {
      "description": "Open the interface in a window"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{a926234f-b54e-4125-aea0-5681ea7fe265}",
      "strict_min_version": "148.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  }
}