Examine source code of YouTube Speed Keys

{
  "manifest_version": 3,
  "name": "YouTube Speed Keys",
  "version": "1.0.0",
  "description": "Change YouTube playback speed with , and .",
  "host_permissions": [
    "*://*.youtube.com/*"
  ],
  "content_scripts": [
    {
      "matches": [
        "*://*.youtube.com/*"
      ],
      "js": [
        "content.js"
      ],
      "run_at": "document_idle"
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "megahed@jshell.dev",
      "strict_min_version": "109.0"
    }
  }
}