Examine source code of no-numbers-yt

{
  "manifest_version": 3,
  "name": "no-numbers-yt",
  "description": "Lock number buttons on youtube",
  "version": "1.0",
  "permissions": [
    "activeTab"
  ],
  "content_scripts": [
    {
      "matches": [
        "*://*.youtube.com/*"
      ],
      "js": [
        "block.js"
      ],
      "run_at": "document_start"
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "no-numbers-yt@example.com",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  }
}