Examine source code of Twitch Mention Alert

{
  "manifest_version": 3,
  "name": "Twitch Mention Alert",
  "version": "1.0.0",
  "description": "Звуковые и системные оповещения при упоминании вашего ника в чатах Twitch во всех открытых вкладках.",
  "browser_specific_settings": {
    "gecko": {
      "id": "twitch-mention-alert@addons.mozilla.org",
      "strict_min_version": "142.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  },
  "permissions": [
    "storage",
    "notifications",
    "tabs",
    "cookies",
    "scripting"
  ],
  "host_permissions": [
    "*://*.twitch.tv/*"
  ],
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "content_scripts": [
    {
      "matches": [
        "*://*.twitch.tv/*"
      ],
      "js": [
        "content.js"
      ],
      "css": [
        "content.css"
      ],
      "run_at": "document_idle",
      "all_frames": true
    }
  ],
  "action": {
    "default_popup": "popup/popup.html",
    "default_icon": {
      "16": "icons/icon-16.png",
      "48": "icons/icon-48.png",
      "128": "icons/icon-128.png"
    },
    "default_title": "Twitch Mention Alert"
  },
  "icons": {
    "16": "icons/icon-16.png",
    "48": "icons/icon-48.png",
    "128": "icons/icon-128.png"
  }
}