Examine source code of FlixSubs

{
  "manifest_version": 3,
  "name": "FlixSubs",
  "version": "3.0.3",
  "description": "Enhance language learning by watching videos with customizable subtitles, instant translations, and a built-in dictionary. Works with YouTube, Netflix, and more.",
  "background": {
    "scripts": [
      "src/pages/background/index.js"
    ],
    "type": "module"
  },
  "action": {
    "default_popup": "src/pages/popup/index.html",
    "default_icon": "icon-128.png"
  },
  "icons": {
    "128": "icon-128.png"
  },
  "content_scripts": [
    {
      "matches": [
        "https://www.netflix.com/*",
        "https://www.youtube.com/*",
        "https://www.coursera.org/*",
        "https://kinopub.net/*",
        "https://kino.pub/*",
        "https://kinopub.cc/*",
        "https://app.plex.tv/*",
        "https://plex.ukrapka.tech/*",
        "https://www.udemy.com/course/*/learn/lecture/*",
        "https://hd.kinopoisk.ru/*",
        "https://www.amazon.de/Amazon-Video/*",
        "https://www.primevideo.com/*",
        "https://www.amazon.de/*/video/*",
        "https://inoriginal.online/*"
      ],
      "js": [
        "src/pages/contentInjected/index.js"
      ],
      "css": [
        "assets/css/contentStyle1723665335517.chunk.css"
      ]
    }
  ],
  "permissions": [
    "scripting",
    "storage",
    "activeTab"
  ],
  "optional_host_permissions": [
    "*://*/*"
  ],
  "optional_permissions": [],
  "host_permissions": [
    "https://translate.google.com/*",
    "http://localhost:8765/*",
    "https://api.lingualeo.com/*"
  ],
  "content_security_policy": {
    "extension_pages": "script-src 'self'; object-src 'self'"
  },
  "web_accessible_resources": [
    {
      "resources": [
        "assets/js/*.js",
        "assets/css/*.css",
        "icon-128.png",
        "icon-34.png"
      ],
      "matches": [
        "*://*/*"
      ]
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{4077aa9d-b853-4913-8e32-27ef408d4c82}"
    }
  }
}