Examine source code of Domic Theme Changer V2

{
  "manifest_version": 2,
  "name": "Domic Theme Changer V2",
  "version": "2.3",
  "description": "Расширенные возможности для сайта domic.isu.ru",
  "author": "G L X V/ARTZ",
  "homepage_url": "https://vk.com/glxv.artz",
  "browser_specific_settings": {
    "gecko": {
      "id": "{9bc1cba2-8582-4731-bb13-f9d78c030f82}"
    }
  },
  "icons": {
    "128": "assets/icons/logo_128.png"
  },
  "permissions": [
    "tabs",
    "*://domic.isu.ru/*",
    "storage"
  ],
  "browser_action": {
    "default_icon": "assets/icons/logo_128.png",
    "default_title": "DTC V2 настройки",
    "default_popup": "popup_menu/popup.html"
  },
  "web_accessible_resources": [
    "*"
  ],
  "background": {
    "scripts": [
      "theme_changer/js/BackgroundWorker.js"
    ]
  },
  "content_scripts": [
    {
      "matches": [
        "*://domic.isu.ru/*"
      ],
      "css": [
        "theme_changer/css/FirstInject.css"
      ],
      "js": [
        "theme_changer/js/FirstInject.js",
        "assets/jquery-3.5.1.min.js",
        "theme_changer/js/DomicThemeChanger.js"
      ],
      "run_at": "document_start"
    }
  ]
}