Examine source code of Better Subscriptions for Youtube™

{
  "description": "Make navigating YouTube's subscription grid easier by hiding watched videos",
  "short_name": "Better Subs",
  "manifest_version": 3,
  "name": "Better Subscriptions for YouTube™",
  "version": "0.27.1",
  "browser_specific_settings": {
    "gecko": {
      "id": "{5dc6dafa-584e-424a-bf90-1d1d8cfa3caa}",
      "strict_min_version": "121.0"
    }
  },
  "icons": {
    "48": "icons/ic_video_library_black_48dp_1x.png"
  },
  "developer": {
    "name": "Oscar Hernandez",
    "url": "https://github.com/OsaSoft"
  },
  "action": {
    "default_icon": {
      "48": "icons/ic_video_library_black_48dp_1x.png"
    }
  },
  "permissions": [
    "storage"
  ],
  "host_permissions": [
    "*://*.youtube.com/*"
  ],
  "content_scripts": [
    {
      "matches": [
        "*://*.youtube.com/*"
      ],
      "js": [
        "util.js",
        "common.js",
        "settingsLoader.js",
        "queries.js",
        "subscriptionCache.js",
        "videos/Video.js",
        "videos/SubscriptionsVideo.js",
        "subs-ui.js",
        "subs.js",
        "vid.js",
        "pageHandler.js"
      ],
      "css": [
        "common.css",
        "subs.css"
      ]
    }
  ],
  "web_accessible_resources": [
    {
      "resources": [
        "images/*",
        "pageContext.js"
      ],
      "matches": [
        "*://*.youtube.com/*"
      ]
    }
  ],
  "background": {
    "scripts": [
      "pages/background.js"
    ],
    "service_worker": "pages/background.js"
  },
  "options_ui": {
    "page": "pages/settings/settings.html",
    "open_in_tab": true
  }
}