Examine source code of Twitch Chat Beautify

{
  "description": "Improve the aesthetics of your Twitch chat.",
  "manifest_version": 3,
  "name": "Twitch Chat Beautify",
  "version": "1.6.9",
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "content_scripts": [
    {
      "matches": [
        "*://*.twitch.tv/*"
      ],
      "js": [
        "TCB.js"
      ],
      "all_frames": true,
      "run_at": "document_end"
    }
  ],
  "permissions": [
    "storage"
  ],
  "host_permissions": [
    "*://*.twitch.tv/*"
  ],
  "action": {
    "default_icon": {
      "16": "icons/icon-16.png",
      "32": "icons/icon-32.png",
      "48": "icons/icon-48.png",
      "96": "icons/icon-96.png"
    },
    "theme_icons": [
      {
        "light": "icons/icon-96-dark.png",
        "dark": "icons/icon-96.png",
        "size": 96
      }
    ],
    "default_title": "Twitch Chat Beautify",
    "default_popup": "popup/popup.html"
  },
  "options_ui": {
    "page": "options/options.html"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "tcb@ed0ardo.com"
    }
  }
}