Examine source code of YouTube Recommendations

{
  "manifest_version": 3,
  "name": "YouTube Music-Only Recommendations",
  "version": "1.0.0",
  "description": "Hides non-music recommendations on YouTube using local, deterministic rules.",
  "permissions": [
    "storage"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "youtube-recommendation-filter@local",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  },
  "host_permissions": [
    "https://www.youtube.com/*",
    "https://youtu.be/*"
  ],
  "action": {
    "default_title": "Music Recommendations Filter",
    "default_popup": "popup/popup.html",
    "default_icon": {
      "48": "icons/icon.svg",
      "96": "icons/icon.svg"
    }
  },
  "options_ui": {
    "page": "options/options.html",
    "open_in_tab": true
  },
  "icons": {
    "48": "icons/icon.svg",
    "96": "icons/icon.svg"
  },
  "content_scripts": [
    {
      "matches": [
        "https://www.youtube.com/*",
        "https://youtu.be/*"
      ],
      "js": [
        "src/defaults.js",
        "src/content.js"
      ],
      "css": [
        "src/content.css"
      ],
      "run_at": "document_start"
    }
  ]
}