Don't worry. You are not alone. This error is one of the most common issues reported by users of the popular browser extension (often referred to as "DownloadHelper"). The "new" in the error message refers to the modern architecture of the extension.
Major sites like YouTube frequently update their code to intentionally break download extensions and third-party tools. Don't worry
Go to your browser's Extension management page ( chrome://extensions or about:addons ). Don't worry