Examine source code of Streaming LAN Cast

{
  "manifest_version": 3,
  "name": "Streaming LAN Cast",
  "version": "0.5.6",
  "default_locale": "en",
  "description": "__MSG_extDescription__",
  "author": "Fabrizio Santi",
  "homepage_url": "https://fabriziosantidev.github.io/streaming-lan-cast/",
  "browser_specific_settings": {
    "gecko": {
      "id": "streaming-lan-cast@fabriziosantidev.github.io",
      "strict_min_version": "140.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  },
  "permissions": [
    "activeTab",
    "storage",
    "clipboardRead",
    "scripting"
  ],
  "optional_permissions": [
    "webRequest"
  ],
  "host_permissions": [
    "http://127.0.0.1:9988/*"
  ],
  "optional_host_permissions": [
    "<all_urls>"
  ],
  "background": {
    "scripts": [
      "browser-polyfill.js",
      "background.js"
    ]
  },
  "action": {
    "default_title": "Streaming LAN Cast",
    "default_popup": "popup.html",
    "default_icon": {
      "16": "icon-16.png",
      "32": "icon-32.png"
    }
  },
  "options_ui": {
    "page": "options.html",
    "open_in_tab": false
  },
  "icons": {
    "16": "icon-16.png",
    "32": "icon-32.png",
    "48": "icon-48.png",
    "96": "icon-96.png",
    "128": "icon-128.png"
  }
}