Examine source code of youtube-quality-changer

{
  "manifest_version": 3,
  "name": "__MSG_extName__",
  "version": "1.0",
  "description": "__MSG_extDesc__",
  "default_locale": "en",
  "permissions": [
    "storage"
  ],
  "icons": {
    "16": "icons/icon.svg",
    "32": "icons/icon.svg",
    "48": "icons/icon.svg",
    "128": "icons/icon.svg"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "youtube-resolution@addon",
      "data_collection_permissions": {
        "required": [
          "none"
        ],
        "optional": []
      }
    }
  },
  "content_scripts": [
    {
      "matches": [
        "*://*.youtube.com/*"
      ],
      "js": [
        "content.js"
      ],
      "run_at": "document_end"
    }
  ],
  "web_accessible_resources": [
    {
      "resources": [
        "inject.js"
      ],
      "matches": [
        "*://*.youtube.com/*"
      ]
    }
  ],
  "action": {
    "default_icon": {
      "16": "icons/icon.svg",
      "32": "icons/icon.svg",
      "48": "icons/icon.svg"
    },
    "default_popup": "popup.html",
    "default_title": "__MSG_actionTitle__"
  }
}