Hello, In order to download 4K from YouTube you need to instal our Ummy Video Downloader.

This useful tool will help you download both HD and MP3 from YouTube: http://videodownloader.ummy.net

Hello, how is the name of your browser?

Hello, please give us more details.
English please.

Hello, due to the change in Mozilla browser, we are no longer able to convert videos in mp3 and merge video and audio flows in mp4.
New API doesn't support functions allowing us to launch video converter and to integrate it with browser.

You can install Ummy Video Downloader to download mp3 and 1080p from Youtube: https://videodownloader.ummy.net

Hi. Thanks for using our resources.

Hello, clean the cache and cookies in your browser.

Install this link: http://download.sf-helper.com/mozilla/helper_last.html

Hello, we do not quite understand you, please describe in more detail.

Hello, Reinstall the extension after an older version is uninstalled. The current version is 7.22:

http://en.savefrom.net/user.php#helper_install